A boat overloaded with passengers in northern Nigeria has capsized, killing 21 people, according to the state rescue agency.

The boat with an estimated 50 passengers on board overturned in strong currents in a river in the Gandi district of Sokoto state on Thursday, reports Al-Jazeera quoting Suleiman Karim of the National Emergency Management Agency (NEMA). 

"Rescue teams recovered the bodies of 17 women and four children on board the overloaded boat which capsized due to strong waves," he said.

He said the other 29 passengers were lucky to make it to the shore.

The passengers were heading to Garin Kare village on the other side of the river to check on their homes, which they deserted following deadly attacks last month by suspected cattle thieves in neighbouring villages.

Thousands of the villagers fled to a makeshift camp after the bandits' attack, in which 32 people were killed and dozens of homes razed.

Boat capsizes are common in Nigeria due to overcrowding and the lack of maintenance for vessels, particularly during the annual rainy season.

In July, 22 traders were killed after their boat capsized in high winds in the Isa district of Sokoto state following a heavy downpour.

Passenger boats in Nigeria, especially in more remote areas, are often poorly maintained and sometimes incapable of navigating rough waters.

But operators with narrow profit margins typically try to put on board an excessive number of passengers to boost income.

BDST: 1835 HRS, AUG 3, 2018
AP