By Jatindra Dash

BHUBANESWAR, India, July 20 (Reuters) - Floods triggered by heavy monsoon rains over the past week have killed at least 36 people in the eastern Indian state of Orissa and inundated half a million homes, officials and witnesses said on Monday.

Rivers breached embankments, submerged hundreds of villages in low-lying areas and damaged thousands of hectares of rice in at least eight of the state's 30 districts, leaving thousands of people stranded.

Much of India in recent weeks has suffered a bad start to the monsoon, whose uneven progress caused drought in some states and floods elsewhere.

Authorities worry the high waters will persist in the flood-prone Orissa, home to more than 36 million people, with more rains expected over the next 48 hours.

"Thirty-six flood-related deaths have been reported so far," Orissa's revenue and disaster management minister, Surya Narayan Patro, told Reuters. "The number of displaced will be more than 5,000."

Patro said hundreds of people had been rescued since Sunday, after rains flooded the homes of an estimated 500,000 people.

The heavy downpour triggered by a low pressure trough over the Bay of Bengal has breached roads and disrupted public transport.

"The flash floods have damaged rice paddy in more than 10,000 hectares," Orissa's agriculture and food production director, Arabinda Kumar Padhee, told Reuters.

TV footage showed people in other areas sheltering on rooftops or wading through knee-deep water in towns.

(Editing by Matthias Williams)

AlertNet news is provided by