About 240 inmates have fled after unidentified gunmen stormed a center in Kogi state in Nigeria, officials say.
It is the second demolition of prisons this year in Nigeria, where dealing with a number of security challenges.
The attackers stormed the prison wall to enter, according to the Reuters news agency.
Nigerian prison officials say the robbers were fully armed and fought a major battle with the guards.
Investigators told local reporters that two security guards had been killed at the Security Custodial Center in Kabba but this was not confirmed.
A search is under way to find the escaped prisoners and gunmen who freed them, the government said.
A total of 294 prisoners were detained in the central security prison, located on the main road linking the cities of Kabba and Lokoja. Many of them had been in prison before being sentenced.
In recent years the Islamist militant group Boko Haram has flocked to the prison to release prisoners several times.
Many prisoners in Kabba are suspected of being Boko Haram militants, but authorities say it was not clear who caused Sunday’s blast.
In April More than 1,800 prisoners released by gunmen set fire to Owerri police station, in southeastern Nigeria. Police in riot gear stormed a rally on Friday, removing hundreds of protesters by truck.
