Gunmen raided a school in northeastern Nigeria on Monday, abducting 36 students and three teachers, authorities announced Tuesday. The attack occurred at the Lassa Day Secondary School in the Askira-Uba area of Borno state.

One teacher was killed during the raid, according to Dauda Iliya, a spokesman for the governor of Borno. The governor has dispatched a high-level delegation to the affected community. The ages of the abducted students, who were taking their secondary school leaving examinations at the time of the attack, range from 15 to 18 years old.

Education commissioner Lawan Abba Wakilbe stated that authorities are collaborating with security agencies and local leaders to secure the safe return of the missing individuals. No group has immediately claimed responsibility for the abduction.

Northeastern Nigeria has been plagued by an insurgency from armed groups, including Boko Haram and its splinter faction, the Islamic State West Africa Province (ISWAP). These groups have caused thousands of deaths and displaced millions in the region and the wider Lake Chad area. Earlier this month, the Nigerian army reported rescuing over 300 people abducted by Boko Haram from Ngoshe, a town near Lassa. In May, a joint operation involving Nigeria and the United States reportedly led to the deaths of 175 ISWAP fighters.