Nigeria’s Boko Haram extremists attacked two villages on the outskirts of the north-eastern city of Maiduguri late Sunday, killing at least 15 people, the military said Monday. The

militants tried to enter the centre of Maiduguri, the provincial capital of Borno state, but army soldiers repelled them, gunning down six armed insurgents and seven suicide bombers, said army spokesman Col. OnyemaNwachukwu.

At least 83 people were injured and are receiving medical attention, he said. Troops prevented the insurgents from entering the center of Maiduguri, but they detonated their bombs in the outlying villages of BilleShuwa and Alikaranti, with one soldier among the 15 casualties, said Nwachukwu. “Troops are still on the trail of the insurgents,” he said. “It is clear that the remnants of the Boko Haram terrorists are hell bent on remaining relevant by attacking soft and vulnerable targets and therefore we call for collective vigilance by all security stakeholders and members of the public.”

Boko Haram, which was formed in Maiduguri, has killed more than 20,000 people in its nine-year insurgency to establish Shariah law in Nigeria.