Gunmen freed more than 260 inmates during an attack on a prison in Nigeria's central city of Jos, officials said, in the country's fourth such raid this year.
The attackers opened fire on guards on Sunday evening, starting a gunbattle that left one guard and nine prisoners dead, the correctional service said.
No one immediately claimed responsibility for the raid in the capital of Plateau State. Regions further north have been plagued by bandits and Islamist militants.
"Some of the attackers and a total of 262 inmates escaped in the melee before reinforcement could come from sister services," the service said in a statement.
Ten prisoners had since been recaptured, it added.
Last month, gunmen attacked a jail in Oyo State and freed more than 800 inmates.
(Reporting by Camillus Eboh, writing by MacDonald Dzirutwe, editing by Andrew Heavens)
