Twenty-five mostly Christian girls have been abducted from a school in Nigeria in an attack that left their vice principal dead.

The girls were seized while sleeping in their dormitories at the Government Girls’ Secondary School in Maga, Kebbi State, during the early hours of Tuesday morning. Only one girl managed to escape.

The school’s vice principal, Malam Hassan, was a Christian and also served as its security officer. It is possible that he was targeted because of his Christian faith.

His wife told AP that three armed men broke into their home on the school grounds.

“They asked my husband, ‘Are you Malam Hassan?’ and he responded, ‘Yes, I am.’ They told him that they were there to kill him,” she said.

No group has claimed responsibility for the attack, but northern Nigeria has faced ongoing unrest from both Boko Haram jihadists and extremists from the Fulani herdsmen tribe.

Maga is located in the northwest of the country, where the population is mostly Muslim. However, the Wasagu/Dankomaga Local Government Area, where the school is located, is one of the most religiously diverse in the state, with several Christian communities.

Seven hundred miles away is Chibok, where 276 schoolgirls were kidnapped in 2014. According to AP, at least 1,500 students have been abducted since then.

Catholic charity Aid to the Church in Need said that local people had begun to feel safer when the attack caught them off guard.

A source reported: “Just when we thought there was a bit of a lull in the killings and abductions, the news of the abduction of around twenty-five girls—we’re not sure of the exact numbers yet—has come as a rude shock, throwing the community into grief.”