A man armed with a handgun attempted to rob a Mexican restaurant in downtown San Carlos on Tuesday night, police said. Officers responded to reports of an attempted armed robbery at the Mi Ranchito taqueria at 660 Laurel St. at about 9:45 p.m.The man had entered the restaurant through a back door and demanded money from the register. When one of the employees yelled for police, he fled without taking anything.The suspect is described as a Hispanic man, 18 to 20 years old, about 5 feet 4 inches tall with a medium build. He was wearing a black jacket with a white shirt and a black beanie. Anyone with information about the robbery is asked to contact the San Carlos Police Department at (650) 802-4277.