At least one university student died and around 40 people were feared dead on Sunday after a crowded bus plunged into a river near the Bangladeshi capital Dhaka, police said.
The bus was packed with around 50 people when the accident happened at Aminbazar, 20 kilometres (12 miles) west of Dhaka.
The bus swerved into the Turag river trapping some 40 passengers inside, chief district administrator Mohibul Haq said.
Army and navy rescuers were called in to help after fire brigade divers failed to locate the bus due to the strong current, Haq said.
"Six hours have passed and still we could not find the bus. I am afraid all the passengers are now feared dead," he said, adding a metal detector was being flown from the southeastern city of Chittagong to help find the bus.
Police said eight people had swum ashore. One of those who emerged from the wreckage, a 23-year-old female student, later died in hospital in the town of Savar, local police chief Mahbubur Rahman said.
Another survivor told reporters that around 50 passengers were inside the bus when it sank into the river.