Three primary schoolchildren have been hacked to death by a machete-wielding man in Borno state.
News reports claim that the man attacked the primary school in a remote village during break-time.
He also wounded a female teacher.
The man was arrested and handed over to the police by members of the community, which is about 230km (140 miles) south of Maiduguri, the Borno state capital.
It is not clear if the lone attacker belongs to any group. The police say the mental state of the suspect is being examined.