An overloaded boat capsized in a river in Sokoto state in northwestern Nigeria, leaving at least 50 people dead, local authorities confirmed on Thursday.

The boat was reportedly carrying people heading to work on farms, but local officials and residents said that at least 40 children were among the casualties.

"I can confirm that so far ​around 40 corpses of children have ​been," said Abdulkadir Yusuf, an area manager of the National Inland Waterways Authority, in a statement to the Reuters news agency.

One resident, Samaila Garba, said his 13-year-old granddaughter was among the dead. He said he had counted at least 42 bodies of victims, most of them women and children.

"During the rainy season, most women and children go to the farm to work," he told the Associated Press.