A North County teen's report about being kidnapped and raped by three men last week turned out to be a hoax she floated in an attempt to keep her parents from finding out that she'd had sex with a man she met on the Internet, authorities disclosed Monday.The 10th-grader told sheriff's investigators she was walking home from school along Melba Road in Encinitas on Friday afternoon when a stranger grabbed her from behind and pushed her into a car occupied by two other men.The 15-year-old claimed the trio drove her through residential streets for about an hour while taking turns sexually assaulting her, then returned to San Dieguito High School and pushed her out of the car.The girl gave detailed descriptions of the supposed assailants, which authorities turned into composite drawings and publicized widely, along with warnings to area families and school officials.News of the supposed crime stirred alarm and concern throughout the North County, prompting many parents to drive their children to school and campus administrators to warn girls against walking by themselves before and after classes.Following "an extensive investigation into the facts, evidence and numerous interviews," detectives determined the teen's story about being kidnapped and raped was a fabrication, sheriff's Capt. Sherri Sarro said.The girl went on to confess to having skipped the final class of her school week, meeting with a man she had been in contact with online and having consensual sex with him."The (girl's) parents had warned their daughter about the dangers of communicating with strangers online," Sarro said. "(She) was embarrassed, ashamed and scared of how her parents would react to her being victimized by someone she had met online."Investigators are now working to track down the man who had illegal sexual relations with the underage girl, according to Sarro.Since admitting her lies, the teen has expressed regret for "creating an atmosphere of fear in the community" and has come to realize that she should have been honest from the start, the captain said.Sheriff's personnel are "somewhat outraged" by the hoax but relieved that the reported crimes did not occur, Sarro told reporters during a late-afternoon briefing at the Encinitas Sheriff's Station.