The chief of the village hit by the explosions said at least three women suicide bombers entered Mandarari's market together in the late afternoon posing as buyers. They then split up, with at least one of them staying in the market while the others went to a nearby camp for people displaced by the ongoing conflict. They detonated their explosives almost simultaneously, Lawan Kalli said.

"Our village is right at the entrance into Konduga town and that is where both the camp and the makeshift market are situated, which made us an instant target point of the insurgents," said Kalli, the village chief.

The injured have been taken to a hospital in Maiduguri, about 30 kilometers (18 miles) away.

The conflict in the region has rendered millions homeless.

No group has claimed responsibility for the blasts. But the suicide attack resembles past attacks carried out by the Boko Haram militants in the region. The insurgency led by the jihadist group has killed 20,000 people and forced some 2.7 million to flee their homes in the last eight years.

Read - Nigeria: Boko Haram refugees find new home

The Islamist group faced several reversals last year, losing large swathes of territory to the Nigerian military. But it has struck back with renewed zeal since June, killing at least 143 people before Tuesday's bombings and weakening the army's control.

Last month, the militants captured an oil prospecting team. At least 37 people, including members of the team, died during the rescue operation.

Stepped-up response

The attack prompted Vice President Yemi Osinbajo, who is standing in for President Muhammadu Buhari while he is on indefinite sick leave, to ask the military to step up its response.

Read - After Boko Haram terror, Cameroon's 'ghost towns' come back to life

The Bloomberg news agency reported that 2,000 special forces troops have been deployed to the region.

In Maiduguri on Tuesday, Ibrahim Attahiru, the army commander leading counterinsurgency operations said: "These specially selected forces with mixed equipment platforms are to achieve the conduct of long-range patrols and ambushes."

ap/jm (AP, AFP, Reuters)