The man shined a flashlight at two girls and presented himself as a police officer as he got out of a sport utility vehicle at about 8:45 p.m. Friday in the 12000 block of Gradwell Street, near Hawaiian Gardens, said Los Angeles County sheriff's Lt. Al Garcia.
Then he punched one girl, who fell to the ground as the man grabbed the other girl, forcing her into his vehicle, Garcia said.
He drove north on Claretta Avenue, then raped the girl before dropping her off near where he first grabbed her, Garcia said.
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The man was described as white, 20-30 years old, bald, about 5 feet 10 inches tall and weighing about 200 pounds. He was wearing a gray sweat shirt with red writing and black sweat pants with white stripes down the sides.
He was driving a white, four-door older sport utility vehicle with tinted rear windows.
Investigators asked anyone with information on the case to call the Special Victims Bureau at 866-247-5877.