At least 52 people died after an overloaded boat carrying farmers and laborers to rice farms capsized in northwestern Nigeria's Sokoto state, authorities said Friday, as rescue teams continued searching waterways for additional victims.

The boat overturned Thursday while crossing a waterway near Gorau in the Goronyo Local Government Area, a rural community where waterways are a vital link to farmland. Local residents said the vessel was carrying more than 70 people, although accounts of the exact number on board varied.

Tukur Abubakar, head of operations for the National Emergency Management Agency in Sokoto state, confirmed Friday that the death toll had risen to 52.

"The death toll has now risen to 52," Abubakar told Anadolu Agency (AA), adding that officials were preparing to meet with local government authorities to identify the victims and contact their families.

The casualty figures had fluctuated sharply in the hours after the accident as rescuers recovered bodies from the water. Sokoto police initially reported 46 bodies recovered and 15 people rescued, with others still missing. By Friday, however, officials and local sources had reported more than 50 deaths, reflecting the difficulty of accounting for passengers in the remote area.