MAIDUGURI, Nigeria -- Witnesses and soldiers said 11 people have been killed as Nigerian troops battled Boko Haram suicide bombers and fighters to repel an attack on the outskirts of northeastern Maiduguri city.

They said nine suicide bombers and two civilians died early Friday, February 17.

It was the fiercest attack in months by Boko Haram on the city which is the birthplace of the Islamic insurgency.

Police said three female suicide bombers detonated vehicles parked at a truck station around midnight. The two civilians died there.

Self-defense fighters said soldiers later fired at gunmen on motorcycles escorting suicide bombers, killing at least six of the bombers.

Soldiers last year drove the Boko Haram insurgents from northeastern towns, but isolated attacks and suicide bombings continue.

The seven-year Islamic uprising has killed more than 20,000 people. (AP)