An unspecified number of students were missing after suspected jihadi militants attacked a secondary school in Nigeria’s northeastern Borno state on Friday, police said, as investigators worked to determine whether anyone had been taken away or whether students had escaped amid the chaos. Nahum Daso, Borno police spokesperson, said several students could not be accounted for after the attack.

Daso told The Associated Press that it was still unclear if students were abducted. He said police could confirm details of many students who “fled for safety during the pandemonium,” while they continued efforts to verify the status of others.

The attack took place early morning in Askira-Uba, a locality that borders the Sambisa Forest, which the police spokesperson described as a stronghold for armed groups. According to Daso, militants carried out the attack from Boko Haram and its splinter group, Islamic State West Africa Province.

Police said a headcount was ongoing to determine whether the incident involved an abduction. Residents reported that militants had already taken dozens of students, a description that has become a familiar pattern in the region as Nigerian authorities confront several armed groups operating across the country.

One resident who spoke to the AP anonymously for fear of reprisals said “Two of my nieces, both under the age of 10, were among the pupils taken away to an unknown destination.” Police said the case remained under assessment as the count continued.

Abduction of school children is common in Nigeria, where the government is battling multiple armed groups, according to Daso’s remarks and broader reporting cited in the same account. Analysts say groups including Boko Haram often target schools for high ransoms because such attacks draw the government’s attention, and last year mass abductions from schools rocked the West African country, with more than 300 children taken in the conflict-battered northern region.