A lone-male robber held up the Subway restaurant at 1311 S. Grand Ave., Glendora.
The robbery occurred when a lone male entered the restaurant shortly after 2:30 p.m. on Thursday. The robber displayed a handgun and demanded cash, said police Lt. Rob Lamborghini.
The man received an unknown amount of cash and ran out of the restaurant. He was last seen running through the parking lot.
Police have no description of the getaway vehicle. The police also had no immediate description of the suspect.