HELENA, Oklahoma - An inmate at a state prison in Helena has been killed by a fellow inmate.

Oklahoma Department of Corrections spokesman Jerry Massie said Sunday that an inmate at the James Crabtree Correctional Center assaulted another inmate about 7:30 a.m. Saturday, resulting in his death.

The Oklahoman reports that Massie declined to offer details about the incident, including the names of the inmates involved, until the department completes its investigation.

The Corrections Department's website says the facility is a medium- and minimum-security, adult male correctional center. It has a capacity of 800 medium and 200 minimum male inmate. The medium-security compound at the facility is dedicated to housing offenders 35 years of age or older.

The correctional center is the only state owned medium-security facility with open dormitory housing.