North-east Nigeria has been hit by its third suicide attack in as many days.
In the latest incident Nigerian officials say four suicide bombers blew themselves up in the city of Maiduguri killing one person and injuring 11 others.
While the Nigerian government says the war against Boko Haram has been won, the Islamist militants, who are believed to be behind the attacks, appear to be ramping up their use of suicide bombers.
Targets often include the sprawling camps where civilians are sheltering from the violence.
A recent Unicef report said more than 100 children had been used by the militants as bombers since 2014.
Most of the children were girls targeting military checkpoints or public places.
By Martin Patience