A boat carrying over 100 passengers sank in Nigeria's north-central Niger State, leaving at least 29 people dead, rescuers said on Wednesday.

The State Emergency Management Agency (SEMA) said in a statement that 29 bodies were recovered and 50 people were rescued, while two were still unaccounted for.

News agency Reuters cited a local government official as saying that the death toll was rising and had reached as high as 60.

How did the boat sink?

The accident took place around 11 a.m. local time (10 a.m. UTC) on Tuesday.

The boat had left Tungan Sule in the Malale district and was heading toward Dugga.

It hit a submerged tree stump near Gausawa community in Borgu Local Government Area and capsized.

"The cause was attributed to overloading and collision with a tree stump," SEMA said.

Accidents occur frequently on Nigeria's busy river networks. They are usually caused by overloading, poor maintenance of vessels and failure to comply with safety norms.

Edited by: Wesley Dockery