Suspected members of the Boko Haram sect attacked the Government Secondary School in Mamudo Saturday, opening fire on students and burning some of them alive, said military Joint Task Force spokesman, Lt. Eli Lazarus.
An English teacher at the school died after he was shot in the chest.
About 1,200 students attend the boarding school. Dozens of them were shot at as they tried to flee into the bush during the attack. Many did not immediately return after the attack ended.
The incident has caused some students at boarding schools in the area to leave for home despite school being in session, Nigeria's Channels Television reported.