By Sorcha O'Callaghan, HPG research fellow, and Sara Pavanello, HPG research officer.

The crisis in Gaza raises serious questions about the means and methods of warfare in densely populated areas. Past experiences in Sarajevo, Grozny and Baghdad show how the conduct of war in contexts of high civilian concentration intensifies the consequences for civilian populations. The likelihood of casualties is bound to be higher; damage to civilian infrastructure more likely and in contexts where civilians coexist alongside combatants, distinguishing between the two is problematic.

It is difficult to imagine a more extreme example than Gaza, which is home to 1.5 million people packed into one of the world's most densely populated areas. Israel's blockade on Gaza following the takeover by Hamas in June 2007 has sealed the territory and dramatically tightened restrictions on the movement of people and goods in and out. Gazans are trapped in the violence that has gripped the territory since Dec. 27 and are effectively denied one of the most basic civilian responses to conflict: to flee. The consequence has been catastrophic for civilians, with an estimated 910 dead and 4,250 injured as of Jan. 12. As the conflict continues to intensify, there is mounting evidence that both the Israeli government and Hamas are using war tactics that contravene International Humanitarian Law (IHL).

IHL sets out the rules of war, restricting means and methods to limit its effect on those who are not participating in the hostilities. It requires that a distinction be drawn between civilian and military targets; that precaution is exercised to prevent incidental damage to civilians and civilian objects, and that any such damage is proportionate to the anticipated military advantage gained. Warring parties should, to the extent possible, avoid deploying near densely populated areas and evacuate civilians under their control from the vicinity of military targets. These rules apply irrespective of the reason for the conflict or the justification for the resort to armed force.

For its part, Hamas has indiscriminately targeted Israeli civilians and made it hard to distinguish between civilian and military targets. Particular concerns have been raised about its use of civilian premises for military activities. But the presence of militants within the civilian population does not deprive that population of their protected status, and as such does not justify the indiscriminate and disproportionate methods adopted in the Israeli offensive.

Reports indicate that Israel has repeatedly targeted civilian locations (such as schools and homes) and has been charged with deploying disproportionate force. Human rights organisations have claimed that the Israeli military are using civilians as human shields. A specific incident where approximately 100 civilians were directed into a shelter by the Israeli military which was subsequently shelled leading to the deaths of 30, was described by the UN High Commissioner for Human Rights as bearing the 'hallmarks of war crimes'. Places of refuge have been attacked, which means that even within Gaza options for safe flight are severely constrained. Those wounded in the warfare have also repeatedly been denied the evacuation and care that IHL demands.

As the occupying power, Israel has a responsibility to ensure life-saving assistance is provided to the affected population. However, the World Health Organisation has warned that the health sector is on the point of collapse; aid workers are raising serious concerns about the potential collapse of the sewage and water system; and people are finding it increasingly difficult to find food and basic necessities. In this context, the daily three-hour temporary ceasefire agreed on Jan. 7 allows little respite to the civilian population. Reports from the ground indicate that the temporary ceasefire merely gives people the chance to bury their dead; to search for food and basic needs; and allows industrial fuel to reach the power plant.

Even humanitarian agencies delivering aid to the beleaguered populations have come under Israeli fire during the lull and despite prior agreement with the Israeli authorities. Resulting deaths and injury to aid workers prompted the UN Relief and Works Agency (UNRWA) the leading UN agency on the ground, to temporarily suspend its operations on Jan. 9. While Israel states that the temporary ceasefire allows a 'humanitarian corridor', this time-bound mechanism is simply insufficient to allow the large-scale humanitarian assistance needed. Secure and unfettered humanitarian access is an urgent priority.

The unfolding humanitarian catastrophe in Gaza is intensifying an already acute crisis, brought about by Israel's blockade of the territory since 2007. Before the current war, 56 percent of Gazans were already food insecure and over 70 percent were dependent on food aid. According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), the prolonged blockade 'created a profound human dignity crisis, leading to widespread erosion of livelihoods and a significant deterioration in infrastructure and essential services'.

In June 2007, the World Bank warned of a potential 'irreversible economic collapse' of the strip. These severe restrictions not only harm militant groups, but collectively punish the entire population of Gaza; once again in violation of IHL. Life-saving assistance alone will be insufficient to counter the effects of these restrictions. Ending the economic blockade imposed on the territory must be a central tenet of the resolution of the current crisis.

Israel itself has acknowledged the difficulty of distinguishing between combatants and civilians, stating that specific military options have not been pursued when the likelihood of collateral damage is considered too high. Some of the alleged tactics, such as the use of human shields are illegal in any context. Others become unlawful as a result of being employed in such a highly populated and closed territory where it is almost inevitable that a disproportionate level of harm to civilians and civilian infrastructure will result.

Whether the Israeli Government is judged unable or unwilling to observe the laws of war in this context, the result is the same for ordinary Gazans. The plan to further expand the offensive into Gaza's main population centres carries an even higher likelihood of disproportionate impact on civilians. Hamas also bears a responsibility to cease its indiscriminate attacks on Israeli civilians. A ceasefire must be agreed.

Despite the delays and silences amongst Western and Arab governments, and abstention by the USA, the international community needs to ensure that there is independent investigation of the alleged violations of international law and war crimes, particularly as access to the territory by independent journalists and human rights actors is restricted. Failure to identify and punish those responsible for unlawful actions sends a message that future violations will also be ignored. Justice and accountability demand otherwise.

For research reports and further analysis on protection by humanitarian actors, visit the Humanitarian Policy Group's website at: http://www.odi.org.uk/hpg/protection_practice.html

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