Kazakhstan's Justice Ministry says 16 prisoners died when they blew themselves up after an abortive attempt to break out a jail in the southern town of Balkhash.

The ministry said in a statement Tuesday that the prisoners mounted an armed assault on a sentry post and then fled to a garment factory within the jail. One prison guard was killed in Monday's attempted breakout.

Justice officials say the prisoners died when they detonated an oxygen canister as special forces approached the building.

Authorities say the prisoners were serving sentences for grave crimes, including robbery, murder and rape.