KADUNA, Nigeria — Dozens of people were feared dead after a boat carrying mostly women and children returning from a religious festival capsized in northern Nigeria, a local emergency official and residents said on Wednesday.

The accident happened around 8:30 p.m. (1930 GMT) on Tuesday when the wooden boat packed with nearly 300 passengers sank in the River Niger, Abdullahi Baba Arah, head of Niger State Emergency Management Agency, said.

Rescue workers and volunteers from Niger’s rural Mokwa local government area had rescued 150 people, he added.

“The search and rescue operation is still ongoing to locate more survivors,” Arah said in a statement.

Ismaila Umar, who leads an association of boat skippers in Mokwa, told Reuters that chances of finding survivors were slim.

This would be the second such major disaster in Niger state in 18 months after more than 100 people were killed in another boat accident.

Overcrowding and poor maintenance are responsible for most boat accidents on Nigerian waterways.