The attack took place shortly before 11 o’clock on Sunday night (local time), while 294 detainees were in the detention center.
A militant group has stormed a jail in the central Nigerian state of Koji , releasing dozens of detainees, a prison spokesman said on Monday.
The militants have not been identified, but many locations in central and northwestern Nigeria have been targeted by terrorists and criminal gangs in recent years.
According to Nigerian Penitentiary spokesman Francis Enobore , 240 detainees have been released.
The attack took place shortly before 11pm on Sunday night (local time), while 294 detainees were in the detention center , including 224 pre-trial detainees.