Nigerian officials say at least six people have been killed as four teenage girls detonated explosives worn on their bodies on the outskirts of Maiduguri city.
The National Emergency Management Agency says the blasts early Wednesday in the Borno state capital killed the four bombers and two others. They also wounded 16 people.
The statement says the blasts occurred near Muna Garage, a common target of Boko Haram extremist attacks in recent months.
Suicide bombings by teenage girls trained by Boko Haram insurgents have become a strategy of the extremist group in the past couple of years.
Over 200 teenage girls have lost their lives in the attacks in northeast Nigeria.
Boko Haram's seven-year insurgency has killed more than 20,000 people and caused a massive humanitarian crisis in the region.