Armed attackers have stormed a federal prison in Nigeria, killing one guard and freeing 118 inmates in a new assault demonstrating the instability in the nation.
The attack on the prison happened at Koton-Karifi, a town in Kogi state just south of Nigeria's central capital Abuja.
The gunmen attacked at night, fighting through the prison gate and killing one guard, said a prisons spokesman. Those inside the prison escaped in the fighting, with 118 inmates known to be missing.
However, local prison official said guards still had not completed a head count and did not know how many prisoners actually were inside the prison at the time of the attack. The government said an investigation into the attack had begun.
"One does not really know why" the gunmen attacked, prisons spokesman Kayode Odeyemi said. "It might be that some of the armed robbers are trying to free the armed robbers there awaiting trial."
The prison held armed robbers and kidnappers. Odeyemi did not know if the prison held any members of a radical Islamist sect known as Boko Haram, which has been plaguing the country with violence over the last year.
Boko Haram launched a similar massive prison break in Bauchi state in September 2010 that freed about 700 inmates there. The style of the latest attack, which apparently used explosives and heavy gunfire, matched that of the previous attack by the sect.
Members of the sect have been blamed for killing at least 286 people this year alone. Its leader, Abubakar Shekau, says the violence is aimed at avenging Muslim deaths, freeing imprisoned members and pushing for strict Shariah law across multiethnic Nigeria, a nation of more than 160 million people.
No group immediately claimed responsibility for the prison attack. If Boko Haram carried out the attack, it would be the farthest strike south the group has made. Nigeria is largely split between a Christian south and a Muslim north. Much of Boko Haram's previous attacks have taken place largely in the north.
Nigeria's prisons remain overcrowded and understaffed, with the majority of those imprisoned awaiting trials for years that will probably never come.