An armed man robbed the Starbucks shop in the 1800 block of Oakdale Road about 6:30 p.m. Sunday, Modesto police reported.
The man ordered a coffee drink and then took an unknown amount of money from a cashier, Lt. Scott Blom said.
Two officers who were in the area chased the man into a nearby apartment complex but were unable to find him, he said. They did find the handgun believed to have been used in the robbery.
The suspect was described as a white man in his middle- to late 20s, standing 5 feet 9 inches and weighing about 185 pounds. He was wearing a dark beanie and red hood, Blom said.