Hundreds of Boko Haram militants were reportedly killed during the offensive that began about a month ago.
According to NTA, the man's nationality is yet to be disclosed.
"The man is under custody and providing positive information", a soldier was quoted as saying.
Hundreds of Boko Haram militants were reportedly killed during the offensive that began about a month ago. Many of the fleeing terrorists were also captured alive.
The military source further said: "Hundreds of Boko Haram captives, including men, women and children have been freed and taken to safety.
"All I can tell you is that no big Boko Haram commander is alive in the Sambisa; we are in control of the forest.
"It took months of planning and mapping because of the size, difficult weather and other factors in the Sambisa Forest."
According to the source, it took the military time to clear out the terrorists' last hideout because they were using thousands of innocent villagers as human shield.
It was learnt that 4,200 troops were deployed to the forest through various fronts.
"The 151 Battalion of the Nigerian Army advanced into Sambisa through the Banki-Darul Jamal axis, the 27 Battalion advanced through Mafa, the 152 Battalion advanced through Pulka, while the 222 Battalion approached the dreaded forest through the Maiduguri axis," another soldier, who participated in the operation was quoted as saying.
He added that, "when mine detectors cleared the way, troops moved in to confront the insurgents, who were equally well armed with sophisticated fighting equipment."
President Muhammadu Buhari had on Saturday, December 24, announced the military's victory over the terrorists. He commended the gallant soldiers for their courage and patriotism.