An undercover sting involving a young policewoman has helped catch a suspected serial rapist thought to have lured unsuspecting girls to bogus job interviews before sexually assaulting them. Police launched the sting after being contacted on Saturday by a 17-year-old schoolgirl who said she had been raped by the man earlier that day. Nude pictures of girls found on the man's electronic devices suggest there may have been as many as 10 women and girls involved. 'It is possible the other victims did not come forward because they had been photographed nude and threatened by the attacker,' one police officer said. Last night, detectives were studying the man's phone records in an attempt to track down other victims. Police believe he found his targets on internet discussion forums and lured them with the promise of well-paid work. 'Investigations show that the victims were offered work in karaoke bars as PR girls in the bogus recruitment,' the officer said. 'They were told they were only required to drink and sing with customers, but promised they would receive HK$200 an hour or HK$800 a day.' On agreeing to attend an interview, the girls would be taken to a guest house or a short-time love hotel where they were raped or sexually assaulted, the officer said. The man's tactics came to light when police were contacted by the secondary school student, who had agreed to attend a job interview on Saturday afternoon. After meeting the man in Mong Kok, she was taken to a short-time hotel in Tung Choi Street and raped. After talking to her parents, she reported the crime at Yuen Long police station. Mong Kok crime squad officers took over the case on Monday, and a young female officer posed as a job-seeker and contacted the man online. The suspect, who matched the girl's description, was arrested when he met the undercover officer in Fa Yuen Street on Monday night. Yesterday, a group of plain-clothes officers escorted the hooded and handcuffed man to the Tung Choi Street love hotel to reconstruct the alleged crime. He was being held for questioning last night and had not been charged. Police are appealing for other victims to contact officers on 2398 6268 or 2398 6200. Mong Kok's deputy police commander, Superintendent Anna Tsang Yim-sheung, warned job-seekers to be realistic and cautious. 'They should be aware of dubious recruitment, especially for high-paid jobs that do not require any skills, academic qualifications or work experience,' she said. She urged job hunters to go with a companion to interviews if necessary. Police figures show eight rape reports in January this year. There were 91 reports of rape last year, an 18.8 per cent drop from 112 reports in 2010.