Rescue officials say at least 35 people have drowned after a boat packed with passengers capsized in northeastern Bangladesh, the AP news agency has reported. 20 people are still missing after the accident, according to local officials.

Officials say the boat carrying about 80 people capsized late on Saturday on the River Surma,  in Sunamgang district, about 175km northeast of the capital Dhaka. The boat was headed towards Itna from Bholaganj, and was carrying about 50 passengers.

Only five or six male passengers on the boat were able to swim ashore.

Matiur Rahman, a rescue official at the scene, said 35 bodies have been recovered so far. Most of the dead are women and children, and rescuers are using torch lights to locate the 20 people who are still missing.

Local government official Abul Hashem told media that the boat sank after hitting a sand-laden cargo vessel at around 9.30pm local time (3.30pm GMT). The collision occured at Alipur.

Rescuers have been sent to the remote location to look for survivors, but rescue efforts are being hampered by poor weather and logistical issues.

Source: Al Jazeera and agencies