The group had earlier claimed responsibility for the attack on Kuje Prison in Abuja.
The Islamic State-backed faction of Boko Haram, the Islamic State West Africa Province (ISWAP), formerly known as Jamā'at Ahl as-Sunnah lid-Da'wah wa'l-Jihād, has vowed to attack more prisons in Nigeria and other parts of the world.
The group had earlier claimed responsibility for the attack on Kuje Prison in Abuja.
SaharaReporters on Tuesday reported that the facility was under attack by gunmen.
According to a source, the terrorists invaded the facility around 9:05 pm and operated till 1:30am on Wednesday morning.
He added that over 800 inmates including terrorists escaped during the attack by gunmen.
However, ISWAP in a video released on Wednesday claimed responsibility for the attack.
In the video, the terrorist sect showed some of its men shooting their way into the facility.
The terror group in a post added that its fighters who attacked Kuje prison were divided into three groups.
The first group stayed at the prison gate, the second one raiding the prison facility while the last one was tasked with blocking the nearby roads.
ISWAP added that its fighters would continue attacking prisons in different parts of the world.