The small vessel was ferrying passengers Friday on the Meghna river, close to the town of Gazaria in the central Munshiganj district, when it collided with a barge laden with sand to be used for construction.

While some passengers managed to swim to safety as the wooden boat went down rapidly, many others remain unaccounted for, according to officials involved in the rescue effort.

"Divers have pulled 12 more dead bodies from the sunken vessel," district police chief Mohammad Shahabuddin told AFP, adding that the ferry had been recovered and would be searched for more bodies. "The death toll is now 14."

The exact number of people aboard the ferry was uncertain as passenger lists are often not maintained properly in Bangladesh and many travellers buy tickets on board.

Police said that the ferry was carrying around 100 people, with 40 people feared missing.

Nasir Hossain, who participated in the rescue operation on Friday using his own boat, said that he and others helped pull 13 people out of the water.

"I heard a bang as a sand-laden barge hit the boat in the middle of the river and saw the overcrowded boat sink quickly," Hossain told a local television channel.

Bangladesh has a history of boat disasters as a result of poor safety standards and frequent overloading of vessels.

Last March 147 people were killed when a passenger vessel sank in the Meghna river after colliding with a cargo ship.

Ferries are the main form of transport in Bangladesh, a low-lying country that is subject to frequent flooding and where the road network is rudimentary.

However many of the vessels that plough the 230 or so rivers that traverse the country date back to before independence in 1971 and overcrowding is frequent.

Naval officials have said more than 95 percent of Bangladesh's hundreds of thousands of small and medium-sized boats do not meet minimum safety regulations.