About 20 gunmen on motorbikes raided a Nigerian federal prison, freeing all but one of the prisoners, the BBC reported.
At least one warden is reported to have died in the assault which took place at At 7 p.m. Nigeria time Wednesday evening, but many details still remain unclear.
One hundred and nineteen inmates have been reported missing, but prison officials do not know exactly how many prisoners were inside prior to the attack, local prison official Hadijha Aminu told the Associated Press.
The prison, located in the small town of Koton-Karafi in the state of Kogi, is said to have held mostly armed robbers and kidnappers, most of whom were awaiting trial.
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No group has claimed responsibility for the attack. Based on the location of the attack and the inmates freed, speculation that the attack was the work of the radical Islamist group Boko Haram has mostly subsided.
Although the attack was tactically and stylistically similar to the September 2010 prison break in which Boko Haram freed 700 prisoners, it would be the farthest south that the group has ever carried out an attack. Nigeria Prisons Service spokesman Kayode Odeyemi could not confirm whether or not the prison held any members of the group.
Nigerian prison conditions have been called "appalling" by Amnesty International; most are packed to the brim with inmates and are understaffed.
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