The Borno attack occurred in two different schools.
Reports from Maiduguri, the Borno State capital, said some gunmen on Monday attacked two schools and shot dead four teachers, while four pupils sustained injuries.
Daily Trust reports that the teachers were shot in two separate attacks.
In the first attack, witnesses said three gunmen stormed Ali-Alaskiri Secondary School in Mafoni ward of Maiduguri and shot dead a teacher at the school while a pupil was injured by a stray bullet.
In the second incident, three teachers were shot dead by another set of gunmen inside the Exams and Records office of Mafoni Day Secondary School while three pupils were injured by stray bullets.
The spokesperson of the JTF, Sagir Musa, could not be reached for comment.