Nigeria-based Islamist militant group Boko Haram has said it was behind last week’s kidnapping of hundreds of schoolboys in the north-western Nigerian state of Katsina.
More than 300 pupils are unaccounted for, but others managed to escape.
The authorities had previously blamed “bandits” for the attack.
Boko Haram has been notorious over the last decade for school kidnappings, including in Chibok in 2014, but these have taken place in the north-east.
In an audio message about the abductions, its leader Abubakar Shekau said “what happened in Katsina was our responsibility” and that his group opposed Western education.
This year hundreds of people in Nigeria’s north-west region have been killed in attacks by what authorities have called criminal gangs, but until now it has been unclear whether they had links with Boko Haram.
The militant group has waged a brutal insurgency since 2009, mostly in north-eastern Nigeria. Tens of thousands of people have died and millions have been forced from their homes.
Activists have criticized President Muhammadu Buhari, whose home state is Katsina, for mishandling the security operation against the militants.
Some have accused him of not showing empathy to the victims and families thereafter a video shared online on Tuesday showed him visiting his farm.
“It’s absolute incompetence and an uncaring, indifferent ruling class that does not understand what it means to govern,” former Nigerian Education Minister Oby Ezekwesili told the BBC’s Newsday programme.
“Here we are as a country just completely showing ourselves as completely unserious when it comes to the matter of human life especially that of our children, ” she said, accusing the government of rebranding “terrorism as banditry”.