KEBBI, Nigeria (AP) — One of 25 schoolgirls abducted from a school dormitory in northwestern Nigeria’s Kebbi state has escaped captivity and returned home, the school principal told The Associated Press on Tuesday.

The girls were abducted when gunmen attacked a high school in northwestern Nigeria before dawn on Monday, taking the 25 girls and killing at a staff member at the school.

The student who escaped fled forests and arrived home late Monday, hours after the kidnapping at the Government Girls Comprehensive Secondary School, said Musa Rabi Magaji, the school principal.

One other student, who was not among the 25 confirmed abducted, also escaped in the minutes that followed the attack, the principal told the AP.

“One is part of the 25 abducted (and) the other one returned earlier,” Magaji said. “They are safe and sound.”

Mass school kidnappings have been rampant in northern Nigeria, where dozens of armed gangs of mostly nomadic herdsmen and, more recently, jihadis, operate. Schools are often targeted by the gangs to gain more attention, analysts have said.

No group has taken responsibility for the incident but analysts and locals say it could be one of several gangs that often target schools, travelers and remote villagers in kidnappings for ransoms.

Authorities have said they include mostly former herders who have taken up arms against farming communities after clashes between them over increasingly strained resources.

Analysts and residents blame the insecurity on rampant corruption that limits weapons supplies to security forces, the failure to prosecute attackers, and porous borders that ensure steady weapons supplies to gangs.