PATNA/DHAKA: At least 50,000 people in India have refused to abandon their homes in flood-ravaged northern Indian despite pleas by authorities to evacuate, an official said on Sunday.

Newspaper advertisements also urged thousands of flood survivors on Sunday to go to one of 77 state-run camps set up in Saharsa district in impoverished Bihar state, where clean drinking water, food and medical care was available.

At least 50,000 people have refused to leave their homes in the district, one of the worst-affected areas in Bihar, said Prataya Amrit, a state disaster management official. Towns and villages in the flooded area are home to about 1.2 million people.

Rescue workers have evacuated about 900,000 villagers, but with river levels falling by up to two feet over the last few days, thousands began to return to their homes, Amrit said.

The Kosi River, which flows down from the Himalayas in neighbouring Nepal into India where it joins the Ganges River, burst its banks on Aug 18 and dramatically shifted course, moving dozens of miles to the east.

It turned hundreds of square miles (kilometres) of land in Biharinto a giant lake.

On Saturday, government engineers began digging a new channel to correct the course of the river and plug the mile-long breach in the embankment.

Disaster officials have not said when it would be safe for villagers to return, and displaced residents may have to remain in camps for several months. Most areas will likely remain flooded until monsoon rains taper off in November, officials say. The government has set up more than 250 relief camps throughout the inundated region and rushed about 900 doctors and medical supplies there.

Already hundreds of cases of pneumonia, diarrhoea and high fevers have been reported. Doctors started immunisation drives on Saturday in the shelters to counter fears that waterborne diseases will spread as the number of camp residents grow.

Authorities have only confirmed 38 deaths, but it is widely believed the final toll will be much higher.

Meanwhile, at least 600,000 people have been stranded and some 14,000 are sheltering in relief centres after floods across Bangladesh dramatically worsened, a minister said on Sunday.

Disaster management minister AM Shawkat Ali told AFP that the army had been called in to help rescue efforts in the worst hit districts as the number of trapped people soared.

“So far 23 districts have been affected by flooding. Some 14,000 people in the worst-affected Sirajaganj and Bogra districts took shelters in relief centres,” he said. Relief chief Zillur Rahman said the Jamuna river had breached its banks in Bogra and washed away dozens of villages.

Interim government head Fakhruddin Ahmed visited affected areas on Sunday morning and distributed relief among the victims, he said.

Bangladesh is criss-crossed by a network of 230 rivers, most of them tributaries of the Ganges and Brahmaputra.

The low-lying country suffers annual floods, with at least a fifth of the country submerged each year. In July and August last year, flooding killed more than 1,000 people and nearly half of the country was under water, forcing millions to flee their homes.