LAGOS, Nigeria (AP) — Rebels from the Boko Haram extremist group claimed responsibility yesterday for abducting hundreds of boys from a school in Nigeria’s northern Katsina State last week in one of the largest such attacks in years, raising fears of a growing wave of violence in the region.

More than 330 students remain missing from the Government Science Secondary School in Kankara after gunmen with assault rifles attacked their school Friday night, although scores of others managed to escape.

The Government and the attackers are negotiating the fate of the boys, according to Garba Shehu, a spokesman for Nigerian President Muhammadu Buhari.

“The kidnappers had made contact and discussions were already on, pertaining to the safety and return” of the children to their homes, said Shehu on Twitter during talks with Katsina Governor Aminu Masari. Neither official said whether the negotiations are with Boko Haram or another group.

Masari said security agencies “deployed for rescue operations have also informed us that they have located their position”.

The Daily Nigerian said it received an audio message from Boko Haram leader Abubakar Shekau claiming the abduction, although there has been no independent verification of its authenticity.

The Islamic extremist group has carried out mass abduction of students before. The most serious took place in April 2014, when more than 270 schoolgirls were taken from their dormitory at the Government Secondary School in Chibok in north-eastern Borno State. About 100 of the girls are still missing.

In February 2014, 59 boys were killed during a Boko Haram attack on the Federal Government College Buni Yadi in Yobe State.

In the audio message about Friday’s attack, Shekau said his group abducted the schoolboys because Western education is against the tenets of Islam.

More than 600 students attend the school. Many were able to escape during a gunfight between the attackers and the police, according to state police spokesman Gambo Isah.

Students corroborated this account with various news agencies, saying many of them were also rounded up and forced to walk to a nearby forest, where some were also able to flee.

Several armed groups operate in northern Nigeria, where Katsina State is located. It was originally believed that the attackers were bandits, who sometimes work with Boko Haram.

Bandits have operated in the north-west region for some time, and kidnappings have increased in recent years. Amnesty International says that more than 1,100 people were killed in the first six months of 2020 in violence related to attacks by bandits.

If Boko Haram is proven to be behind the abduction, it could mean a new wave of religious extremism is on the rise in Nigeria.