The exact number of people on board may never be known

The triple-decked ferry, the MV Nasrin-1, had been travelling from the capital, Dhaka, to Lalmohan when it hit turbulent waters near the town of Chandpur just before midnight.

Initial reports suggest the ferry may have been overcrowded, not just with passengers, but also with a big cargo of rice and vegetables.

Bangladeshi shipping minister, Akbar Hussein, said around 200 people had managed to swim to shore.

Passengers swarmed the ferry as another scheduled on the route cancelled its itinerary without prior notice Shipping ministry official

"I think about another 400 people are still in the ferry," he told the BBC.

"The ferry capsized in a river which has a tremendous current."

Chandpur is where three rivers, the Padma, Meghna and Dakatia merge.

Nose-dived

Hundreds of anxious relatives and survivors lined the shores or joined rescue teams.

A salvage ship attempting to reach the Nasrin-1, which is thought to be lying 60 metres (200 feet) down, was severely hampered by the strong currents.

Many of the survivors had swum to safety to a nearby ferry terminal, although one later died in hospital.

Others were rescued by local fishermen and ferries in the vicinity.

One survivor, Samir Chandra Adhikari, said he was on the roof of the vessel and dived overboard when it started to sink, swimming 100 metres to the riverbank.

"The ferry turned aside suddenly. Within moments it started nose-diving and I jumped into the river."

Nearly 220 survivors were taken on to their destinations aboard another ferry after receiving treatment at local hospitals.

Passenger lists

Dhaka's senior river transport official, Abul Hossain Chowdhury, said the ferry had an official capacity of 429 passengers, but was "definitely overcrowded".

Ferry accidents have killed thousands in the past 20 years

He said initial investigations suggested the accident happened after one of the ship's two engines stopped, sending it out of control.

An official at the ministry of shipping said passengers had "swarmed the ferry as another scheduled on the route cancelled its itinerary without prior notice. In this case, the rules were grossly violated".

It is unlikely that the exact number of passengers on board will ever be known as ferries in Bangladesh rarely have passenger lists or issue tickets.

The chief government administrator of Chandpur district, Abdur Rab Hawlader, told the BBC rescue vessels had as yet found no trace of the ferry.

A ferry that sunk in the same location in 1994 has never been found.

Nearly 300 people have died in ferry accidents this year in Bangladesh prior to the latest disaster.