SANTA ANA, Calif. (KABC) -- Police in Santa Ana are warning the public of a sexual assault predator on the loose who lures his victims by posing as an undercover officer.Officials released a composite sketch and vehicle description of the suspect, who committed three sexual assaults between August 2015 and January 2016.Each occurred on Harbor Boulevard near Hazard Avenue, where the suspect lured the victims into his car after telling them that he's a police detective.He then drives the victim to an isolated area and is "extremely violent in his assaults," said Cpl. Anthony Bertagna with the Santa Ana Police Department.The suspect is described as a white male in his mid-40s with a muscular build. He is about 5 feet 7 inches tall, with blonde or gray hair and blue eyes. He drives a newer model four-door blue Nissan or an older two-door black Subaru.Police asked anyone with information to contact contact Detective Corporal Javier Aceves at (714)245-8542 or Orange County Crime Stoppers at (855)TIP-OCCS.