The Nigerian military says its solders have thwarted an attack by three female suicide bombers from the Boko Haram extremist group, fatally shooting two as they tried to detonate their explosives near people who have fled their homes because of fighting.

Col. Sani Kukasheka Usman of the Nigerian army said in a statement that two civilians were injured in the attack by Islamic extremists early Tuesday on the outskirts of Monguno town in northeast Nigeria.

He says some of the bombers' explosives detonated even though they had been shot, while the third bomber blew herself up in a different area where no one was harmed.

Separately, the Nigerian military says it killed four suspected Boko Haram members in an ambush in the Kukawa area of the country's northeast.