Five teenagers from Tel Aviv sexually assaulted a female classmate during a period spanning six months in 2008, police said on Thursday, following the completion of an undercover investigation.The girl, now 17, was 15 when the alleged offenses occurred.RELATED:'Nice girls don't get raped'Girl, 17, allegedly raped near Ben Avigdor street in TATA rape suspect may be serial offenderThe boys have all been arrested and released to house arrest, with the exception of one suspect – believed by youth officers to be the orchestrator – who remains in custody after appearing before a Tel Aviv Youth Magistrate.“The offenses were committed in gardens, bomb shelters, in the suspects’ homes – wherever they could get away with it,” a police source close to the investigation told The Jerusalem Post on Thursday.“In addition to severe sexual assault, the suspects also threatened to harm the victim if she uttered a word to anyone. They are suspected of extortion through threats.“It began when one of the teenagers, a ringleader, sexually assaulted the girl,” the source continued. “He then brought other friends, and gradually the group expanded to five. They would take turns exploiting her.” A number of suspects admitted to carrying out the offenses, while others have denied any involvement, police said. All five suspects were indicted on Thursday at the Tel Aviv District Court.The arrests come after a number of similar incidents were uncovered by police in recent months.In March, 13 youths were arrested by police in Tel Aviv on suspicion of gang-raping a teenage girl over the course of three years.In May, four boys aged 13 to 17 were arrested in Bat Yam on suspicion of subjecting a 12-year-old girl to repeated group rape over two years.