More than two hundred people were believed missing after a boat sank in Democratic Republic of Congo's waters on Lake Tanganyika on Thursday night, a senior Tanzanian official said on Sunday.

U.N. radio in Congo, Radio Okapi, said on Friday that at least 26 people had died and authorities had rescued 221 people after the boat sank in the vast lake near the village of Tembwe, 90 km (around 55 miles) south of the town of Kalemie.

Radio Okapi said it was not clear how many people were travelling in the boat, which was carrying passengers between Katanga and South Kivu provinces in eastern Congo.

However, Tanzanian authorities said the vessel had been carrying some 500 people.

"It was carrying about 500 people and about 230 people have been rescued so far," Deputy Inspector General of Police Abdulrahman Kaniki told Reuters by telephone, attributing the information to the head of the Tanzanian marine police.

Congo's government spokesman and regional officials were not immediately available for comment.