Thirty-six people are missing after a boat sank in the Congo river on the outskirts of the capital Kinshasa, DR Congo police said on Sunday. The whaler-type boat was travelling from Mai Ndombe province when it sank in Maluku commune, about 100 kilometres from its destination, Kinshasa. "The cause of the accident is not yet known," police spokesperson Colonel Pierrot-Rombaut Mwanamputu told AFP. Seventy-six people were rescued from the river. Lake and river transport is widely used in Democratic Republic of Congo as the highway system is poor, but accidents are common, often caused by overloading and the unsafe state of vessels.<br/> In the vast majority of accidents, passengers are not equipped with life jackets and many cannot swim.