He will likely be released on parole because of good behaviour, with a quarter of his sentence not served, reports news agency TT.

A prison psychological report says that Lindberg was not fully responsive to treatment, and that there is an "elevated" risk that he will again commit sexual violence. A criminology professor says to Swedish Television that many prisoners sentenced to time-limited terms have no real desire to take part in treatment, and would rather just sit out their time in jail.

Lindberg was in charge of training thousands of police officers, as principal of the National Police Academy 1989-1997, and he was then county police chief in Uppsala 1997-2006.

He was arrested in 2010 with a bag full of sex toys, on his way to meet one of his victims, a 14-year-old girl. He was convicted of aggravated rape, assault, paying for sex and also of procuring girls for other sex buyers. Some of his attacks were described as involving "sadistic sexual violence". Lindberg admitted buying sex, but denied the other charges.

"In most of the cases, I have had a fairly equal relationship, despite paying for sex," said the former police chief during the court case.