Pervert Mark Hanson, 50, preyed on young children Mark Hanson with police after his arrest / Picture: Supplied Source: Supplied IT'S every parents' nightmare. Two little friends walking home from school along a residential street, stalked by a stranger in a car, dragged into a bushland reserve and raped. Sydney father Mark Hanson, 50, already behind bars for seven and a half years for trying to grab two young girls, was yesterday charged with another four similar attacks in the city's northern suburbs across five years. His victims twice included two girls walking home together, it was claimed. Detectives from the state's Sex Crimes Squad, who discovered the new allegations, believe there may be more victims yet to come forward. "He has been operating under the radar for years," one senior police source said outside court. Hanson was working as a travelling salesman for Wattyl paint when he was arrested at his Castle Hill home in July last year. The father of a 22-year-old son went on to plead guilty to trying to abduct a six-year-old girl as she rode her scooter in South Turramurra in February last year and to threatening a 14-year-old girl at knifepoint on a bush track in Westleigh two months later. Both girls escaped. In September this year, the sexual predator was jailed for seven and half years with a non-parole period of five years and three months. According to court documents filed with Parramatta Local Court, is it alleged that Hanson's offending went back to 2007 when two eight-year-old friends were forced into bushland at Fred Caterson Reserve at Castle Hill early in the evening of August 30. Police allege both girls were raped. It will be alleged that he used his work Holden Commodore to follow his victims. On November 3, 2011, it is alleged that he abducted an 11-year-old girl at Holland Reserve, Glenhaven, for his "sexual gratification" and photographed her for "pornographic purposes." On December 2, 2011, two other friends aged nine and 10 were on their way home from school when they were allegedly confronted by Hanson armed with a silver pistol. They were abducted for his "sexual gratification" and at Aluba Reserve, South Turramurra, they were indecently ­assaulted and then photographed "for the purpose of child abuse material," it is ­alleged. It is alleged that in December last year, he raped a 17-year-old girl at Hall Street, Turramurra. Hanson's lawyer Shaun Titmarsh did not apply for bail for his client yesterday. Hanson, who is in Parklea Jail, was not required to attend the court and his case was adjourned to February 6. "I think these allegations shake parents to the core," Australian Childhood Foundation CEO Joe Tucci said ­yesterday. They make children and the community in general feel less safe. Mark Hanson is arrested by police / Picture: Supplied Source: Supplied