The Nigerian army on Wednesday confirmed the rescue of one of the Chibok schoolgirls abducted in 2014 by Boko Haram militants in the northeastern state of Borno.

Army spokesman, Sani Usman, said in a statement that the girl, Amina Ali-Nkeki, was among a group of people rescued by Nigerian troops at Baale community in Borno state.

He however didn't state when the girl and other hostages were freed.

A total of 276 girls were abducted from their secondary school dormitories in Chibok town in April 2014, for which Islamist group Boko Haram claimed responsibility.

About 57 girls managed to escape later, but more than 200 remain missing.

Usman said operations inside the Sambisa Forest in Borno state on Tuesday cleared Boko Haram fighters out of their Njimia camp and hideouts in nearby areas in the forest, killing 15 militants and freeing 41 hostages, mostly women and children.

"It is gratifying to note that no casualty was recorded by our troops through the conduct of this operation," he added.

Boko Haram has killed more than 10,000 people, mostly in northeastern Nigeria, since it launched its campaign of violence in 2009.

The Nigerian army has made progress in the fight against Boko Haram in the past year, retaking most of the areas previously under Boko Haram control.