The attackers, armed with rifles, stormed the Government Girls Comprehensive Secondary School in Maga town around 4 a.m. and exchanged gunfire with security personnel before breaching the perimeter fence, police spokesperson Nafiu Abubakar Kotarkoshi said in a statement.
Vice Principal Hassan Yakubu Makuku was shot dead while trying to resist the gunmen, and another staff member was wounded, he added.
Police said additional tactical teams, soldiers and local vigilante groups have launched a search-and-rescue operation and are combing nearby forests and suspected escape routes.
Northwest Nigeria has experienced repeated mass abductions by armed groups seeking ransom. Despite government security measures, schools remain frequent targets.
In 2014, Boko Haram abducted 270 schoolgirls from Chibok in Borno State — an incident that drew global condemnation. Many of the girls have since been freed, but dozens remain missing.