Updated

An Arizona prison complex is on lockdown after a fight broke out among 400 inmates.

Arizona Department of Corrections spokesman Bill Lamoreaux says the staff was able to quickly stop the fight that broke out at 9:45 a.m. Sunday at the Whetstone Unit of the Arizona State Prison Complex in Tucson.

Two prison staffers suffered minor injuries, while five inmates were brought to hospitals with injuries. The extent of the inmates' injuries wasn't immediately available.

The prison is investigating the cause of the fight.

Nearly 1,250 prisoners are housed in the Whetstone Unit. No inmates from the prison's other seven units were involved in the fight.

It's unclear exactly how long it took prison staff to end the fight.