A police truck lies overturned in a flooded field

Relief operations are being stepped up in the eastern Indian state of Orissa amid concerns about the spread of water-borne diseases following last week's cyclone.

Reports from the region say field clinics and mobile hospitals are filling up, and that government and private hospitals in the state capital, Bhubaneswar, are being swamped with people from outlying districts.

"The deaths now are a combination of both starvation and gastro-enteritis - food shortages and dirty water," Julian Francis of the International Committee of the Red Cross said.

Mass cremations are planned to stop decaying corpses spreading epidemics.

But with tens of thousands of dead livestock littering areas affected by the cyclone, contaminated water remains a major concern.

The BBC's Daniel Lak, who has visited areas outside the capital, says medical charities and the local authorities are encouraging people to boil drinking water, but the supply of chemicals needed to guarantee water purity is still limited.

Shanty towns have begun springing up along roads as people hope to get supplies of food and medicine from passing aid convoys.

Rising death toll

The number of people now confirmed dead as a result of the cyclone has doubled.

The official overseeing rescue and relief operations in the state of Orissa, RN Padhi, put the figure at 3,435, up from 1,715. He said the figure could rise to 5,000.

He said thousands of corpses were still to be recovered and were decomposing in waterlogged fields.

An air force officer involved in relief operations said volunteers would be dropped in inaccessible regions in an attempt to prevent decomposing bodies causing further damage to health.

"We will carry people with kerosene and drop them in batches and allow them to burn the carcasses," Group Captain HPS Natt said.

Soldiers and international aid workers have been using rowing boats to deliver food and medicine to millions still cut off by vast lakes of floodwater.

The Orissa state government has also started air-dropping medicines along with instructions on how to use them.

"It will be weeks before the debris and waste can be really cleared up," said one official. "By that time epidemics are inevitable."