Pakistan's western border areas are racked by violence as separatists and pro-Taliban militants fight government forces to try to extend their control. Hundreds of thousands of people have been displaced by the fighting, many of them out of reach of aid agencies.

The main areas affected are North West Frontier Province (NWFP) and the semi-autonomous Federally Administered Tribal Areas (FATA) which have a strong Taliban presence, and Baluchistan where separatists are seeking greater political autonomy and control over local mineral resources.

The rest of Pakistan has also been subject to sporadic attacks by Islamist militants. Opposition leader Benazir Bhutto was assassinated at the end of 2007 in an attack blamed on Pakistani Taliban leader Baitullah Mehsud.

The United States regularly carries out missile strikes against al Qaeda and Taliban leaders in the border areas.

The U.S. administration of President Barack Obama has been pressing Pakistan to take firm action against Islamist militants as part of a drive to end a military stalemate in Afghanistan.

The Taliban and other militant Islamist groups operating in Pakistan are fighting internal conflicts, regional battles in Afghanistan and Kashmir and, in some cases, global jihad against the West. Some are connected with al Qaeda. They are loosely co-ordinated, but often share resources and recruits.

They include Afghan Taliban and al Qaeda militants, who fled Afghanistan when U.S.-led troops ousted them in 2001, and Pakistani Taliban and other Pakistani groups who share a similar hardline version of Islam.

Although the Pakistani Taliban are mostly active in the tribal belt along Pakistan's western border, other militant Sunni groups are based in the country's political heartland in Punjab province. The largest of these, the Lashkar-e-Taiba, has been accused of organising an attack on Mumbai in November 2008. These groups are believed to provide logistics and other help to al Qaeda and the Taliban. Two of these groups, the sectarian Lashkar-e-Jhangvi and Kashmir-oriented Jaish-e-Mohammed have been blamed for bomb attacks inside the country, while the Kashmir-oriented Lashkar-e-Taiba has not been known to attack Pakistani targets.

Afghan militants used Pakistan's border areas in the 1980s as a base for fighting Soviet troops in Afghanistan. They were helped by foreign fighters, including men like Osama bin Laden who later became al Qaeda leaders. The so-called mujahideen were backed by the United States and Saudi Arabia among others.

After the Soviets withdrew, mujahideen factions formed a government in Afghanistan but tensions remained and the Pashtun-dominated Taliban faction began fighting for control of the country, taking over Kabul in 1996.

Since 2001, Afghan militants have used Pakistan's border areas to orchestrate their insurgency against the Afghan government and the U.S. and NATO forces supporting it.

Taliban groups now control large swathes of the Federally Administered Tribal Areas (FATA) and, before a millitary offensive launched in April 2009, controlled parts of Northwest Frontier Province (NWFP). They also have bases in Baluchistan.

The spread of Taliban influence in the border areas has been blamed on years of neglect and poor governance, as well as insecurity in neighbouring Afghanistan.

The North West Frontier Province (NWFP) province was formed in 1901 under British India, and divided into Settled Areas and Tribal areas. It has a Pashtun-majority population, history and culture.

Armed conflict between government troops and pro-Taliban militants has caused massive displacement, especially in Swat, Buner and Lower Dir districts.

The Swat Valley - once a major tourist attraction - became the scene of some of the worst fighting in Pakistan when the army launched a large-scale offensive in April 2009. Nearly two million civilians were displaced, and hundreds of thousands more were trapped by the fighting and out of reach of external help.

People began slowly returning home in July after the Pakistan Army said it had cleared the Taliban out of Swat.

In the 1990s, cleric Sufi Mohammad took up arms to impose sharia law in the Malakand region, which includes Swat district. He led thousands of fighters to Afghanistan in 2001 to help the Taliban resist the U.S.-led invasion, and was arrested on his return to Pakistan. Pakistani authorities released him in 2008 in a bid to defuse another uprising, led by his son-in-law Fazlullah, who has ties with other Pakistani Taliban factions and al Qaeda.

Fazlullah called his men to arms after a military assault on the Red Mosque in Islamabad in mid-2007. The mosque had been taken over by extremists who were stockpiling weapons there in a bid to impose Islamic law.

The army deployed troops in Swat in October 2007 and used artillery and gunship helicopters to reassert control. A civilian government came to power in 2008 and tried to reach a negotiated settlement, but a peace deal failed in May 2008 and fighting escalated. The militants gained control of almost the entire valley and unleashed a reign of terror, killing and beheading politicians, entertainers, soldiers and opponents. They banned female education and destroyed nearly 200 girls' schools.

But the military has also been accused by local people of deliberately targeting civilians perceived to be sympathetic to the Taliban - a charge vehemently denied by the military. For more on this read: Civilians suffer as Pakistan army targets Taliban.

In February 2009 Pakistan authorities agreed to introduce Islamic law in Malakand region, dismantle all security checkpoints and release captured militants in return for peace. The decision was strongly condemned by the United States, which had made continued flows of aid conditional on Pakistan containing the Taliban groups.

The militants announced a ceasefire but refused to give up their arms and soon pushed into Buner district, also part of Malakand and only 100 km (60 miles) from Islamabad. Amid mounting concern at home and abroad, security forces launched an offensive in April 2009 to expel the militants.

Afghan Taliban leaders are believed to use Peshawar, capital of NWFP, as a base despite the heavy presence of Pakistan military and intelligence forces.

Millions of refugees who fled Afghanistan following the Soviet invasion in 1979, settled in NWFP. Many have since returned home.

Pakistani Taliban tribal groups control large swathes of the Federally Administered Tribal Areas (FATA). They draw much of their resources from jihadi groups and their countrywide networks of mosques and religious seminaries, or madrasas.

Since 2001, FATA has become a hideout for al Qaeda and Afghan Taliban militants. The areas of most concern include South Waziristan, North Waziristan and Bajaur. South Waziristan has numerous training camps for suicide bombers and has been described by U.S. officials as the world's most dangerous place.

Pakistan's seven tribal areas (or agencies) were created by the British to serve as a buffer between what was then northwestern India and Afghanistan. A special form of political administration, based on independent jirga (council) systems, was devised to govern the Pashtun tribes which fiercely resisted colonial rule. The British stationed troops in FATA to maintain control, but also granted these areas a semi-autonomous status in return for acquiescence to colonial rule.

The system continued when FATA became part of Pakistan. Pakistan chose not to base troops in the region, but retained the colonial administrative and legal structures - effectively treating FATA's population as separate from other Pakistani citizens.

NWFP's federally-appointed governor administers FATA. It is governed through local proxies - mostly tribal elders - and laws which deprive locals of civil and political rights and the protection of the courts. The tribal elders' loyalty is rewarded with special status and financial benefits.

The military has supported tribal militias to help it fight the religious extremists.

The Pakistani military has been criticised for its tactics, including attacks by helicopter gunships and heavy artillery which have forced thousands of civilians to flee to camps in NWFP.

PACT WITH TRIBAL LEADERS

From late 2003 to early 2005, the Pakistan army focused on hunting down al Qaeda in South Waziristan, later shifting its attention to North Waziristan and Bajaur at the northeastern extreme of the tribal belt.

The heavy handed tactics of then President Pervez Musharraf's government - largely a response to external pressure - were widely thought to have backfired, pushing sympathies further towards the Taliban and fundamentalist Islamic beliefs.

In September 2006, Musharraf's government decided to soften its approach, signing a deal with tribal leaders and pro-Taliban forces. Islamabad agreed to hold off military operations, free prisoners and withdraw from checkpoints. In return, militants promised to end attacks on the army, distance themselves from foreign fighters, and stop movement across the Afghan border.

The deal's supporters said it would empower tribal elders to control militants, although critics argued it would create a sanctuary for the Taliban and al Qaeda.

In the following months, attacks on U.S.-led troops in eastern Afghanistan trebled, and an October 2006 U.S. congressional report said Taliban activities in the border region had increased.

The deal unravelled in July 2007 amid a surge in violence in northwest Pakistan, following the army's storming of the radical Red Mosque in Islamabad in which troops killed 75 supporters of hardline clerics.

North Waziristan militants scrapped the peace deal, arguing that the government had violated it by launching attacks and deploying more troops in the area.

As the pact collapsed, the U.S. president's national security adviser called on Musharraf to take further action against militants in the region, pledging Washington's full support. Violence in North Waziristan and other parts of northwest Pakistan intensified sharply.

The New York Times reported in July 2007 that the United States planned to pour $750 million in aid into Pakistan's tribal areas over the next five years, as part of a campaign to win over the local population. But there were concerns over how effectively the money could be spent on development in such an insecure region.

In August 2008, Pakistani forces launched offensives against al Qaeda and Taliban militants in Bajaur - a major infiltration route for militants entering eastern Afghanistan. The militants were said to include Afghans, Uzbeks and Arabs as well as Pakistani Taliban.

A Pakistani general in Bajaur described it as a "centre of gravity" for Islamist guerrillas and said the conflict in Waziristan was more of a "tribal war", whereas the situation in Bajaur had more "international linkages".

But the Pakistani military's tactics were strongly criticised, including reports that operations forced all schools to close in more than half Bajaur's towns, affecting about 50,000 students. An estimated 20 percent of Bajaur's population was forced to flee, most finding refuge in NWFP, says the Internal Displacement Monitoring Centre.

The government signed a peace deal with tribal militants in Bajaur in March 2009.

Pakistan launched a major offensive in South Waziristan in October 2009 after several months of air and artillery strikes against the Taliban. Tens of thousands of people began to flee the region in May 2009 when the military began massing troops in large numbers in the semi-tribal areas on the periphery of Waziristan.

The United States has also been targeting the region with drone missile strikes, including one in August 2009 which killed Pakistani Taliban leader Baitullah Mehsud. He was replaced by Hakimullah Mehsud who is believed to lead as many as 20,000 pro-Taliban militants in South Waziristan. A majority belong to the Mehsud tribe.

The region is out of reach of most foreign and Pakistani journalists and aid agencies.

Baluchistan lies to the southwest of FATA, bordering both Iran and Afghanistan, and is made up primarily of Baluch and Pashtun ethnic groups. Baluch tribal militants are fighting a decades-long insurgency for greater political autonomy and control over local mineral resources.

Afghan Taliban fighters also operate in the area.

BALUCH INSURGENCY

Tribal militants in Baluchistan have staged several insurgencies since the mid-20th century to fight for greater political autonomy and control over local mineral resources from the Punjabi-dominated authorities. Although the military maintains an iron grip on the region, Baluchistan is often cited by doomsters as the region most likely to splinter from Pakistan. Pakistan has accused India and Afghanistan of backing the Baluch nationalists.

The Pakistan government announced a roadmap in October 2008 for ending conflict in Baluchistan, focusing on redistributing natural resource revenues, a turnaround from Musharraf's strategy in the region. But the military occupation continues, with regular reports of human rights abuses, cited by the Asian Human Rights Commission and the Human Rights Commission of Pakistan.

Baluchistan was not incorporated into Pakistan until 1948, when Pakistani troops moved in, forcing the Khan of Kalat, the monarch who had ruled the area under the umbrella of the British Empire, to give up hopes of independence.

In the mid-1950s, the People's Party, a new nationalist party, was launched by the Prince of Kalat, and in 1972 it joined with the National Awami Party, based in North West Frontier Province, and the Islamist Jamait-ul-Ullema-i-Islam in opposition to the centralising government of President Zulfiqar Ali Bhutto (Benazir Bhutto's father).

Major conflict broke out in 1973 after the intelligence services intercepted a consignment of weapons headed for Baluchistan and Bhutto dismissed the regional government.

Thousands of militants fought the national army, which targeted the Baluch tribes' livestock, their key economic asset. The insurgency dragged on until 1977, when Bhutto was overthrown and the new military regime of General Zia ul-Haq arrived at a political settlement with some Baluch leaders. Around 9,000 people died in the violence.

Conflict flared again in December 2005, following a rocket attack during a visit by Musharraf to the town of Kohlu. This spurred the Pakistani military to launch a major crackdown against nationalist groups in the region.

Since then, militants have regularly blown up gas pipelines, rail tracks and power lines, and launched rocket attacks on government buildings and army bases.

The security agencies have responded by targeting hundreds of Baluch dissidents, including political activists, students, doctors, lawyers, journalists and even shopkeepers.

The Human Rights Commission of Pakistan has cited numerous instances of intimidation, arbitrary arrests, torture, disappearances and extrajudicial killings by security forces and intelligence agencies.

Much of the militant violence is thought to be carried out by a group known as the Baluch Liberation Army (BLA), which was set up in the 1970s. The government has listed it as a terrorist organisation.

Resentment against the central government has grown as infrastructure has been built to exploit the province's rich natural resources, especially gas. The Sui field in Baluchistan's Bugti tribal area produces around 45 percent of Pakistan's natural gas. The province also has significant deposits of uranium and copper.

Development has fuelled local frustration for two key reasons. Firstly, Baluchs feel their province is being increasingly monopolised by non-indigenous migrants attracted by its economic opportunities.

Secondly, there's a widespread perception that the province does not receive a fair share of benefits from the exploitation of its resources. Baluch nationalists say natural gas generates $1.4 billion a year, but Islamabad gives the province only $116 million in royalties.

One major infrastructure project targeted by Baluch militants is the construction of a strategically important port at Gwadar on Pakistan's Arabian Sea coast near the mouth of the Persian Gulf, with the majority of funding coming from China.

Besides calling for a larger dividend from development projects and the exploitation of resources, Baluch militants want more control over their administrative affairs. Analysts say local people have few political channels through which to voice their grievances and demands.

AFGHAN TALIBAN IN BALUCHISTAN

Afghan Taliban groups have had strong links with Baluchistan for years. The Taliban movement, which swept to power in Afghanistan in 1996, sprang mainly from Islamic seminaries established in Baluchistan during the Afghan war. After their defeat by U.S.-led forces in 2001, the fighters regrouped in Pakistan. U.S. generals have often said the Afghan Taliban leadership operates from regional capital Quetta - although Pakistan denies this.

Taliban groups are very active in southern Afghanistan bordering Baluchistan, and it's here the United States is stepping up its offensive against them.

In early 2009 there were media reports the United States might extend its missile attacks in Pakistan to include militant targets in Baluchistan. The United States has assured Pakistan it will not do so, but it is asking Pakistan to station more troops in the area.

Following an army attack on a militant base in FATA's South Waziristan in January 2007, cities around Pakistan were hit by a wave of suicide bombings, including the capital Islamabad, and Quetta and Peshawar in the northwest.

A backlash against the security forces intensified after the July raid on the Red Mosque, confirming fears that unrest in the tribal areas was spilling over into other regions. Nearly 800 people were killed in militant-related violence in the following four months - many in suicide attacks and bomb blasts.

Musharraf imposed a state of emergency in Pakistan in November 2007 citing rising militancy as a key reason. He suspended the constitution, sacked most judges and locked up lawyers. Diplomats said his main aim was to stop the Supreme Court ruling that his earlier re-election as president had been invalid on the grounds he was still army chief at the time. Emergency rule was lifted in December.

Musharraf came to power in a military coup in 1999. He named himself president in 2001, while remaining head of the army, and later granted himself sweeping new powers including the right to dismiss an elected parliament. Parliamentary elections were held in 2002, and Musharraf won a presidential election in 2007.

Hundreds died in the run-up to general elections in February 2008, including opposition leader Benazir Bhutto who was assassinated at a campaign rally in December 2007.

Bhutto's grieving Pakistan People's Party went on to win the elections. Musharraf, under threat of impeachment, eventually resigned in August and was replaced by Bhutto's widower Asif Ali Zardari.

Zardari was sworn in as president in September 2008, and announced a renewed commitment to tackle the militants using a combination of negotiations, economic and political reforms, and military force.

Despite having committed itself to the deeply unpopular U.S.-led campaign against Islamist militancy, the government formally protested against U.S. missile strikes on the border areas soon afterwards.

In both northwest and southwest Pakistan, hundreds of thousands of citizens have fled violence. Calculating the numbers is difficult, because of a lack of access.

There are no government offices dedicated to the displacement issue and no national policies in place, although ministries with health or children portfolios have responded to the crisis in some areas. The government has prevented aid from reaching those displaced in Baluchistan, and insurgent attacks on aid workers in many areas have also made it very difficult for agencies to reach them, says the Internal Displacement Monitoring Centre.

International aid agencies are trying to boost their development activities. The tribal areas in particular have suffered from poor literacy, scarce development funding and the fallout from the instability in Afghanistan.

Pakistan hosts the largest refugee population in the world - nearly 1.8 million Afghans, the majority living in urban areas. Another 3.5 million Afghans have returned home since March 2002, says the U.N. refugee agency UNHCR.

NORTH WEST FRONTIER PROVINCE

A surge of violence in NWFP's Swat, Buner and Lower Dir districts in 2009 forced nearly 2 million to flee their homes. Some sought shelter in the region's displacement camps, which are crowded and offer limited access to clean water and food.

But aid workers say the majority of displaced are reluctant to live in formal camps for cultural reasons, as they feel their dignity is compromised and women cannot strictly observe 'purdah' where they should be separated from men. As a result, many lived in cramped conditions with host communities or relatives.

Men often stayed behind to protect homes and livestock, although this left women and children vulnerable to increased sexual violence and exploitation.

Thousands have slowly begun to return to their homes in Swat after the government said in July 2009 the area was safe.

Many people were also displaced when a massive earthquake hit NWFP and Kashmir in 2005, killing 75,000 people and leaving up to 3.5 million homeless.

NWFP has also been a refuge for millions fleeing fighting in other parts of Pakistan and Afghanistan.

FEDERALLY ADMINISTERD TRIBAL AREAS

The United Nations estimated in September 2008 that 200,000 displaced people in the tribal areas (FATA) were beyond the reach of U.N. agencies.

The UNHCR reported in October 2008 that some 190,000 people had been displaced from FATA's Bajaur area by fighting which began in August. Most sought shelter in NWFP where the former Afghan refugee villages of Katcha Gari and Jalozai (in or near Peshawar) were adapted to cater for some of the displaced. Some fled into eastern Afghanistan. The UNHCR said it could not access most of these areas for security reasons, and relied on government estimates.

Tens of thousands fled South Waziristan from May 2009, when troops began massing in the region ahead of a major military offensive which began in October 2009. The majority fled to NWFP, staying with host families or in rented accommodation.

BALUCHISTAN

Baluchistan displacement dates back to 2005 when the government launched a military offensive against separatists. The number of displaced hovers at about 50-60,000 people. They are living without clean drinking water or health care, and dozens of children have died from malnutrition and disease. The government has prevented aid from reaching the displaced in Baluchistan.

Aid agencies in Baluchistan include the UNHCR, which mainly supports Afghan refugees in the province, and the World Food Programme. But humanitarian and development workers have come up against bureaucratic hurdles when trying to help the local population.

In June and July 2007, Baluchistan, along with Sindh province, was hit by severe flooding that destroyed homes, crops and roads, and temporarily displaced over 2.5 million people. There was criticism of the humanitarian response to this disaster - with aid agencies saying their ability to provide relief was hampered by the government's hesitation in requesting international help.