At least 41 people have died and 49 others have been rescued after a boat capsized on Lake Tanganyika in the Democratic Republic of the Congo.

The vessel was travelling from the port of Kigoma in Tanzania to the city of Kalemie in the DRC when it sank on Thursday near the Congolese village of Mapera. About 100 people and cargo were reportedly on board at the time.

Norris Mulongoyi, the provincial transport minister for Tanganyika province, said search operations were under way to locate the remaining passengers.

A survivor identified as Annie Moyoni told a UN-backed Congolese broadcaster that passengers were awakened at around 1am and found the boat tilting to one side. The cause of the capsizing remains unclear.

The sinking was the second loss of a Congolese vessel on the Kigoma-Kalemie route in less than a month. On August 28, the Congolese vessel MV Pacifique caught fire and exploded at the port of Kigoma while loading fuel. Six crew members were killed and a seventh was reported missing, according to port authorities. The vessel operated between Kigoma and Kalemie and was used to transport fuel.

In July, at least 20 people died when a wooden boat carrying students returning from state exams sank in central DRC.

Boat disasters are common in the DRC, where vessels are often overloaded and lack life jackets. For many residents, travelling by boat is the most affordable means of transport in a country that lacks sufficient infrastructure for its population of more than 100 million.