His account tallies with reports from politicians and survivors of attacks, and it reinforces fears that Boko Haram, once a machete-wielding gang, now poses the greatest security threat to Nigeria's unity and may be growing closer to al-Qaeda affiliates in Africa.
It comes the same week Justice Minister Mohammed Adoke charged that Boko Haram is being influenced from abroad. "Nigeria is experiencing the impact of externally-induced internal security challenges, manifesting in the activities of militant insurgents and organised crime groups which has led to the violation of the human rights of many Nigerians," he said, defending the country's record at a meeting of the United Nations Human Rights Council in Geneva.
The government has failed to respond to requests for comment, but on Thursday night, for the first time, presented an alleged Boko Haram detainee to journalists at a news conference in the northern city of Maiduguri.
The 22-year-old, walking on crutches because of a bullet wound suffered when he was captured in a recent attack, said he was forced to join Boko Haram but that the movement has many willing and educated members.
"We have mechanics, we have welders, we have carpenters, we have professional drivers, we have butchers, security experts, gun instructors and so on," he said, displaying his lack of education by his poor use of Hausa, the local language most common in Maiduguri, where he used to live with his parents. He refused to give his name because he was afraid his former colleagues would target his family.