OCEAN BEACH — San Diego police are probing a gas station robbery in Ocean Beach on Sunday afternoon, during which the suspect reportedly sported a Halloween mask. The suspect struck the Shell station at 4794 Voltaire St. around 4:15 p.m. and indicated he had a handgun, police said. The man demanded cash and fled on foot, according to investigators. The robber is described as a black male, about 5-feet-8-inches-tall with a husky build and a goatee. He was last seen wearing a dark shirt and dark-colored pants. Anyone with information is urged to call the San Diego Police Department’s Robbery Division at (619) 531-2299.