A brutal battle between two groups left 13 dead and another 65 injured on Saturday, according to Al Jazeera. Homemade knives and picks were used between the two rival groups of inmates. The incident started when tone of the groups became fed up with harassment form the other group. Authorities at the prison were able to regain control, but not after a large number of casualties. According to authorities 22 of the 65 injured remain in serious condition.
Concepcion Tovar, head of the state's prison system, said the riot was instigated by an inter-prison gang that had been harassing and robbing other inmates for some time, according to Nigeria News. The battle involved over 100 prisoners, and it is unclear whether guards were involved as well. Other riots in the past have been blamed on the same gang that instigated Saturday's brawl.