Authorities say at least four men were hospitalized after a riot at San Quentin State Prison that involved nearly 200 inmates.

Prison spokesman Lt. Samuel Robinson says in a statement that the four inmates had stab or slash wounds after the melee broke out among 184 men in the prison's dining hall on Sunday night.

Guards stopped the brawl using non-lethal bullets and pepper spray, and found at least 10 weapons made by inmates in the aftermath.

The was no word on what sparked the rioting or further information on the condition of the injured. Robinson says many others had minor injuries, but did not give a number. No guards were hurt.

San Quentin, in Marin County north of San Francisco, is the state's oldest prison and houses nearly 5,000 men, including those on death row.