Police investigating the armed robbery of a service station in Browns Plains overnight have released images of a man they believe may be able to assist with inquiries.

Shortly before 8pm, a man entered the store on Browns Plains Road and selected a can of drink from a fridge.

He then approached the counter, lifted his shirt revealing a knife, and threatened the attendant before fleeing the store with a sum of cash.

He was last seen running east along Browns Plains Road.

The offender is described as Caucasian in appearance, approximately 175cm tall with a slim build.

He was wearing three quarter length blue shorts and a grey long sleeve hooded shirt.