Officials in the Indian tea and oil-rich state of Assam said the fortnight-old flooding had claimed 23 lives there and forced a staggering 1.7 million people from their homes.
They said 150 relief camps had been set up to provide shelter and food to the homeless and troops were working around-the-clock to rescue marooned villagers and reopen roads.
In the past 24 hours, 80 villages were inundated by torrents of water from tributaries of the Brahmaputra River. Tuesday morning alone, three districts recorded rainfall of more than 0.4 inches.
The rains paused Tuesday in parts of eastern West Bengal state where at least 70 people had been killed and 350,000 made homeless by floods or mudslides since last Thursday.
Rescue workers found 20 bodies under debris in the state's Cooch Behar and Jalpaiguri districts, where many villagers had tried to flee across swollen rivers in shallow wooden boats.
''There are definitely more bodies under the debris,'' A.K. Maliwal, a senior police official at the scene, told Reuters. ''We fear the toll (in Cooch Behar and Jalpaiguri) will cross 100.''
Troops carrying medicine, rice and wheat on their heads waded through swirling waters to temporary camps for the homeless.
Relief efforts were slow, however, because sections of road had been swept away and many highways were blocked with boulders from landslides.
Flooding is an annual event in the northeast India, which is said to have the highest rainfall in the world from a rainy season that lasts until September. Roughly 100 million people live in the affected areas.
In northern Bangladesh, meanwhile, the death toll from flooding rose to 15 after six people were drowned or crushed in a house collapse.
Local officials said troops and volunteers had evacuated about 30,000 people, but some 150,000 still were stranded on high ground or the roofs of houses.
Food and drinking water shortages were reported in many areas.
Local reports said that in the tea-growing district of Sylhet, which was flooded for the second time in two weeks, almost 300 people had diarrhoea.
- Reuters - Thomson Reuters Foundation
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