The motorised boat left the town of Kalemie and was heading for the port of Wimbi when it sank on Wednesday.
“Of the 21 passengers aboard, nine were killed, all of them children,” provincial official Joseph Lumona told AFP,
“Another child is reported missing,” he said, adding that the accident happened in “violent winds”.
Such accidents are frequent occurrences in DR Congo, either on the lakes or rivers. The death tolls are often high as boats are overcrowded and old and there is a lack of life jackets.
These problems are exacerbated by the fact that many locals cannot swim.
In September, 20 people were killed when a boat capsized on Lake Edward, another of the African Great Lakes, as they were fleeing fighting between the Congolese army and a militia in the restive North Kivu region.
Lake Tanganyika is the longest freshwater lake in the world and is bounded by four countries — DR Congo, Burundi, Zambia and Tanzania.