Paso Robles police are investigating the Monday armed robbery of the Pacific Premier Bank on 12th Street.

Shortly after 1 p.m., the robber entered the bank armed with a semi-automatic handgun, and demanded cash from one of the tellers. After receiving an undisclosed amount of money, the robber, who was wearing an old man mask, fled on foot down the back alley.

On his way, he grabbed a deposit bag from a customer attempting to enter the bank through the back door.

The man was wearing blue jeans, a white long sleeve shirt, gloves, scarf and a fedora.