A fight broke out Wednesday among more than 100 inmates at an Arizona prison, injuring three inmates and a corrections officer, a corrections official said.

The officer suffered bumps and bruises, and one of the inmates who had a head injury was flown to a Phoenix hospital, said Arizona Department of Corrections spokesman Barrett Marson. The prison was on lockdown, he added.

He said no one suffered life-threatening injuries, and that no weapons were used in the fight.

Marson said the fight broke out around 9 a.m. in a high-security unit of the Lewis prison complex west of Phoenix, and that it was mostly in the recreation yard and the kitchen.

He said the reason why the fight broke out was under investigation.

The Lewis prison near Buckeye was the site of what is believed to be the longest prison standoff in U.S. history.

In January 2004, two inmates took two correctional officers hostage, resulting in a 15-day standoff before they surrendered. It occurred after officers in the prison's kitchen were overpowered by two inmates, and one officer allowed one of the inmates — disguised in a uniform taken from an overpowered officer — into the prison tower.