The 40-seater bus was transporting workers of Arunima Sports Wear Ltd at Jirabo in Savar to the capital.

Eleven people were either rescued by local people or they managed to climb through the bus windows and swam to safety, said an official of Fire Brigade and Civil Defence. However, the local residents put the number of survivors at seven.

A survivor, Jarina, said there were around 45 passengers on the bus. Mohammad Mainuddin, a sub-officer of the fire department said there were 40 to 45 passengers on the bus when it tumbled into the river. He said 11 of them either managed to swim to the shore or were rescued.

However quoting another survivor a witness, Mohammad Israfil, said, "Six passengers managed to get out of the bus and around 20 others were trapped inside. Four of the survivors are identified as Parveen, Julie, Enayet and Omar Faruq.

Tajul Islam, a quality supervisor of the factory, without giving any figure regarding the number of passengers, said the bus was jam-packed with workers when it started from Jirabo, but many of them got off at Savar.

Emdad Hossain, manager of the apparel factory, told The Daily Star, "The bus had only 11 to 12 workers of our factory on it, all of whom managed to swim to safety. The idea that people are missing cannot be correct."

Another survivor however said, "There were over 30 people on the bus since many former workers, who had gone to the factory to get their last month's salary, were also on the bus on their way back home." The driver of the bus is also missing.

Divers of the fire brigade searched inside the sunken bus but could not find anybody dead or alive. "I entered the bus five times and searched thoroughly, but could not find anyone," diver Mohammad Alauddin told The Daily Star.

He said strong current might have carried away the bodies through the bus windows which local people had smashed to rescue the garment workers trapped inside.

Witnesses said the accident occurred as the driver suddenly swerved the bus to the left to let an overtaking car pass by amid drizzles. "As the driver swerved the bus, he lost control of it, and the bus fell into the river with eight feet depth of water just at the western side of Shalepur Bridge around 1:45pm," said a helper of a truck, Mohammad Israfil, who witnessed the accident.

Fire fighters called in a crane of Dhaka City Corporation (DCC) to lift the sunken bus, but it failed to lift the bus as its cable snapped. The officials concerned could not say when they will be able to pull out the bus from the river.

"Hearing screams I turned around and found that a bus was tumbling over the concrete slope of the bridge by the river bank," said a man who was catching fish in the river at the time of the accident.

Hundreds of onlookers gathered at the spot halting traffic on the Dhaka-Aricha highway for about half an hour following the accident.

Many garment workers who work in factories in the area rushed to the spot after getting information about the accident. Tension was mounting among the fellow workers of the missing, who were not very happy with the result of the rescue operation.

Police and Rab personnel were deployed at the spot to maintain law and order.