Arlington police released surveillance camera photos of a man they said robbed someone outside a Valero store last week.
Police said the clerk at the store thought the man, wearing a jacket with no shirt and a large unidentified tattoo across his chest, looked suspicious.
When he left without buying anything the clerk locked the door.
Police said the man then grabbed a handgun from his car and tried to go back in the store. When he couldn't get back in he robbed a person in the parking lot.
Police said they also believe he robbed a person at a nearby Chicken Express.
The man then fled the scene in a white Cadillac, which witnesses said had a large spare wheel on the back and custom rims.