An overloaded wooden boat has sunk in high waves off Cameroon's coast, killing at least 63 people, a government official said Monday. Witnesses said 15 people survived, but at least 20 others were missing and feared dead.

The boat, which was carrying passengers along the coast to Nigeria, sank Saturday night near the Cameroonian village of Mabeta, said Peter Itoe, an official of the local Limbe district reached by telephone. He said 63 of the estimated 100 passengers aboard perished and had been buried.

"We learnt from the survivors that the boat initially carried some 29 people, but was collecting others along the coast as it sailed toward its destination in Oron, Nigeria," Itoe said. "According to the survivors, who are mainly Nigerians, the boat became overloaded with over 100 persons aboard and four vehicles."

Itoe did not say how many survived, but a journalist who visited the scene southwest of the capital Yaounde, Christopher Fon, said 15 people had escaped.

Itoe said high waves splashed into the vessel and began to flood it. That, combined with the weight of too many passengers and goods, caused the boat to tip and sink, Itoe said.

It was not immediately known how many people it was safe for the vessel to carry.

Fon said bodies were found floating along the coast and nearby beaches. They were collected by Cameroonian naval units and buried in six mass graves in Mabeta.