Okah - former member of Mend group - was arrested following car bombings that killed 12 people in capital.
Around 41 people were injured as bombs went off in multiple attacks in the federal capital.
EXCLUSIVE: Witnesses recount suicide blast that rocked Borno State capital on Nigerian Independence Day.
Between four and seven blasts rocked Borno state although government claims Boko Haram is surrendering.
Nigeria celebrates 55 years of independence but is still one of the world's worst places for LGBT rights.
EXCLUSIVE: IBTimes UK speaks with intelligence group on risk that pro-Biafran movement might become violent.
Surrender comes in the wake of 'Operation Lafiya Dole' by Nigerian army.
IBTmes UK speaks with intelligence on the future of Burkina Faso following a military coup.
Three separate explosions have taken place in north-eastern Nigeria, with 90 injured.
Boko Haram suspected as insurgents behind the deadly bombing.
Boko Haram releases audio message after army claims anti-terrorism operation is successful.
IBTimes UK speaks with intelligence on recent statement made by President Muhammadu Buhari.
Unicef reveals the children have been forced to flee their homes to escape the terror group.
IBTimes UK speaks with counter terrorism expert on strategies to tackle terrorism in Nigeria
Buhari promised he would fight Boko Haram, end corruption, promote youths employment.
Nigeria and neighbouring countries are engaged in a joint offensive to defeat terrorists.
Thousands of legitimate users blocked by Nigerian mobile network operators in terror clampdown.
A Suicide bomb detonated in north-east Nigeria killing at least six and injuring at least 41 others.
Villagers surprised by jihadists on motorcycles were killed in most recent attack on Kukuwa-Gari village.
Suspected pirates killed four soldiers and one policeman at military base in Bayelsa State.
IBTimes UK spoke with Fa'ash on its work to help poor Nigerians and prevent youths from joining Boko Haram.
Nigerian army announces new task force, comprising some 8,700 troops, ready to take over ongoing fight.