Video released by an Oklahoma sheriff's office shows an ex-volunteer deputy pointing a stun gun at a suspect weeks before he fatally shot an unarmed man.

The video recorded by Tulsa County sheriff's deputies shows Robert Bates drawing the weapon on a man lying on the ground in March 2015.

It also shows Bates briefly drawing his firearm before re-holstering it as a deputy yells "stop, stop." It's unclear where Bates was aiming the gun. The sheriff's office said Friday the deputy was only yelling at Bates to be quiet.

Three weeks later, Bates fatally shot Eric Harris while working with deputies. Bates has said he mistook his firearm for his stun gun. He's charged with second-degree manslaughter.

The video, first reported by The Frontier and KOTV-TV, was released by the Tulsa County Sheriff's Office.