The worst floods to hit southern India in a century have made 2.5 million people homeless and left 250 dead.
At least five million people are crammed in temporary government shelters after heavy rains last week triggered flooding that swamped millions of acres of cropland.
"These are the worst floods in 100 years," said Dharmana Prasada Rao, Andhra Pradesh's minister for revenue and relief.
Relief officials used helicopters and boats to drop off rations and plastic sheets to hundreds of marooned villagers in Andhra Pradesh and Karnataka, the worst-hit states.
Officials and relief agencies said flood victims – including about 2.5 million people from Karnataka and Andhra Pradesh who have lost their homes - were now sheltered in over 1,200 temporary camps.
On Monday, rescue workers used about 300,000 sandbags to fortify weakening embankments of the Krishna river that flows close to Vijayawada, a city of about a million people in Andhra Pradesh and an important trading centre.
More than 50,000 people were trapped by floodwaters near the city, according to The Times of India, with many villages along the bank under 2m of water.
Rescue workers had earlier moved more than 200,000 people living close to the river and an alert was raised in about 100 villages situated along it.
Officials said vast areas of agricultural land, including sugarcane and paddy fields, were under water.
Media reports quoted officials as saying that billion of dollars were needed for relief and reconstruction.
PHOTO CAPTION
An aerial view of the flooded city of Raichur on October 3.
Al-Jazeera