A passenger ferry caught fire overnight in the southern Philippines, killing at least 10 people, officials said on Thursday.

The ship was at sea, near an island in the southern province of Basilan, when the fire occurred on Wednesday evening, the Philippine Coast Guard said. The cause of the fire was not immediately clear, and the coast guard said an investigation was underway.

Maritime accidents are common in the Philippines, an archipelago of more than 7,100 islands where travel by sea is the cheapest mode of transportation.

Last year, seven people died after a passenger ferry carrying 124 passengers caught fire soon after setting off from Polillo Island, east of the Philippine capital, Manila. More than a hundred other people were rescued.

This is a developing story.