Prisoner on the run in WA's Mid West

A prisoner has escaped from a minimum security facility in Western Australia's Mid West region.

Steven Arthur Brockman, 37, was discovered missing from Greenough Regional Prison on Sunday night.

Police say he is unpredictable and should not be approached.

Brockman is described as being dark skinned, 175cm tall, of slim build, with short dark hair and brown eyes and was last seen wearing prison greens.