Another 21 Chibok schoolgirls kidnapped by Boko Haram from their school in 2014 have been released.
The girls were brought to Yola International Airport in Yola, Adamawa State capital around 3pm on Thursday.
The Nigerian Army troops rescued over 1,880 civilians from a Boko Haram redoubt in the restive northeast in the past week and arrested hundreds of insurgents, a military commander said on Wednesday.
The Sambisa forest, covering about 1,300 square kilometres (500 square miles), is a stronghold of the notorious jihadist group, who kidnapped more than 200 schoolgirls in 2014.
“During our operations in the period 14-21 December 2016, a total of 1,880 civilians were rescued from Boko Haram enclaves,” Major-general Leo Irabor said in a statement after a news conference in the northeastern city of Maiduguri on Wednesday.
Irabor added: “564 Boko Haram terrorists were arrested while 19 others surrendered to our troops. Also, seven suspected kidnappers and 37 foreigners were equally arrested.”
He said several Boko Haram fighters were killed and a cache of arms and ammunitions was discovered in the operation, part of a military campaign launched last year to clear the area of the jihadists.
Hundreds of civilians, including women and children, have also been freed in neighbouring Cameroon, said Irabor. Eight jihadist suspects were subsequently identified among them and taken into custody.
Boko Haram seeks to impose a hardline Islamic legal system in Nigeria’s mainly-Muslim north.
It has been blamed for the deaths of at least 20,000 people since 2009. The rebellion has also displaced some 2.6 million people, sparking a humanitarian crisis in the region.
The United Nations has warned that the affected region faces the “largest crisis in Africa”.
The UN estimates that 14 million people will need outside help next year because of the ongoing violence, particularly in Borno State in northeastern Nigeria, the country’s jihadist heartland.
Since early 2015, Nigerian military with the support of a regional force, have recaptured a swathe of territory from the insurgents.
But sporadic attacks on civilian soft targets have continued in the volatile region, including the use of female suicide bombers.
On December 9, two female suicide bombers killed 45 people and wounded 33 others when they detonated their explosives in a crowded market in Madagali, which has been previously targeted.
While there was no immediate claim of responsibility, the blasts bore all the hallmarks of Boko Haram.