The incident happened on Saturday night near the Jilli axis, close to the border between Borno State and Yobe State, a region at the centre of a long-running insurgency, News.Az reports, citing Reuters.

Nigeria’s Air Force said it had carried out an operation targeting militants from Boko Haram in the area, but did not mention a market being hit. It has not responded to further requests for comment.

Authorities in neighbouring Yobe state later confirmed that an air strike had taken place near a market where civilians had gathered. Brigadier General Dahiru Abdulsalam said people travelling from Geidam local government area to attend the weekly Jilli market were among those affected.

Local councillor and traditional leader Lawan Zanna Nur Geidam described the incident as “very devastating”, saying that more than 200 people had died. Witnesses and an international humanitarian official also confirmed the strike and the likely high death toll.

The Yobe State Emergency Management Agency said it had received preliminary reports of casualties affecting traders at the market and had activated an emergency response.

One survivor, Ahmed Ali, said he was injured in the blast. Speaking from hospital, he described how panic spread as people tried to flee. “I became so scared and attempted to run away, but a friend dragged me and we all lay on the ground,” he said.

The region has been heavily affected by years of violence linked to Islamist insurgency, which has killed thousands of people and displaced millions more.