Over five million people have been marooned or left homeless in low-lying parts of eastern India, Bangladesh and Nepal as river waters flooded huge swathes of land.
Overflowing rivers, snakebites and landslides have killed dozens of people in South Asia and forced millions from their homes in the worst monsoon flooding in years, officials said today.
Thousands were stuck on rooftops, waiting for military helicopters to rescue them or provide food.
The chief minister of India's northeastern Assam state, where two million have been made homeless, appealed for international aid, saying the state was battling the worst floods in recent years.
Floodwaters have swept away power lines, embankments, railway tracks, swamped highways and destroyed dozens of small dams in oil-and-tea-rich state Assam.
More than 150 people have died in the region since the start of the month as heavy rains triggered flooding. Most of the latest deaths came from mountainous Nepal where landslides and swollen rivers have killed at least 24 people since Sunday.
Many people have died of snakebite as the floods have driven snakes into homes. The floods, which have affected one-third of Nepal's area, have hit the impoverished nation's main rice crop.