SPOKANE — Authorities says an inmate died in his cell at Spokane County Jail after a possible attack marking the fifth inmate death at the Spokane detention center in the past 12 months.

The Spokane County Sheriff’s Office says a corrections officer found the inmate lying face down on his bunk, not moving on Wednesday night.

The sheriff’s office says attempts to revive the man were unsuccessful and he was pronounced dead shortly after.

The Spokane County Medical Examiner’s Office is working to determine the man’s cause and manner of death.

The Spokesman-Review reports five inmates have died at the detention facility since last June.

Three inmates took their own lives and one man died in the jail’s booking area of causes that remain to be determined.