Twenty-two children have died and more than 130 have been injured after a school building collapsed in Nigeria’s central Plateau state, local officials say.

Saint Academy in the state capital Jos caved in while students were in class on Friday morning. Children were left trapped under the debris.

Volunteers used excavators, hammers and their bare hands to break through the piles of concrete and twisted iron rods to reach many of those trapped.

Police told reporters that at least 22 children had died in the collapse, with many more receiving treatment in local hospitals.

The school is believed to have more than 1,000 pupils.

Local resident Abel Fuandai told the BBC that his friend’s son had been killed and said “the scale of the tragedy is frightening”.

The cause of the collapse is not known but residents said it came after three days of heavy rains in Plateau.

Speaking from hospital, injured student Wulliya Ibrahim told AFP: “I entered the class not more than five minutes, when I heard a sound, and the next thing is I found myself here.

“We are many in the class, we are writing our exams,” he said.

Resident Chika Obioha said he had seen a number of dead bodies and that dozens of people had been rescued.

“Everyone is helping out to see if we can rescue more people,” he said.

“Devastated by the tragic loss of young lives at Saint Academy,” Unicef Nigeria representative Cristian Munduate wrote on X.

“Children full of dreams were writing exams when the school building collapsed. Deepest condolences to families affected.”

There have been several major building collapses in Nigeria in recent years, with observers blaming a mix of bad workmanship, poor quality materials and corruption.

In 2021, at least 45 people were killed when a high-rise building under construction collapsed in a wealthy Lagos neighbourhood.