Dozens of people were feared to have drowned Friday when a bus packed with about 50 wedding guests plunged into a river in western Bangladesh, news reports said.

The bus was boarding a ferry when it toppled over into the Chitra River in Narail district, 70 miles west of the capital, Dhaka, the United News of Bangladesh news agency and the ATN Bangla television station reported.

Only 10 people, including the groom, were able to swim to shore, while the rest, including the bride, were feared trapped inside the sunken bus, the reports said. No bodies had been recovered.

The groom, Deepak Biswas, was taken to a hospital in a state of shock, said Sultan Mahmud, a local journalist.

Mahmud said Biswas, his family members and relatives were traveling home with his bride, Lipi Mallick, whom he had married in a neighboring district only hours earlier.

Navy and police divers were trying to locate the sunken bus, but their work was hampered by darkness, a police official said.

The bus was thought to be about 45 feet under water, the official said on condition of anonymity because he was not authorized to speak to the media.

Fatal bus accidents, often blamed on faulty vehicles and unskilled driving, claim about 4,000 lives each year in the impoverished South Asian nation.