Richard W. Valentino, 20, was arrested Sunday night on Montauk Highway in East Quogue after a witness provided a description of the suspect and the vehicle he was driving, police said.
Police had responded to a call at the King Kullen store in Hampton Bays on Sunday after a woman said she returned from shopping to find her pocketbook had been stolen from her car in the parking lot.
Police said further investigation revealed that Valentino also had stolen pocketbooks from other vehicles in the area.
He is charged with three counts of grand larceny, police said. Arraignment information was not available.