A SEX menace who used the internet to prey on teenage girls was behind bars last night.

Robin David Blewett was finally caught after he lured a 16-year-old girl, from York, into his home.

The 41-year-old's arrest by detectives from North Yorkshire led to a nationwide inquiry with a team from the Child Exploitation and Online Protection Centre.

An inquiry found a further four teenage victims and catalogue of more than two million pornographic photographs and child abuse images on computers and discs in his home.

The inquiry also revealed he had used the internet to compile a database of more than 500 named teenage girls.

He targeted unsuspecting, naive and vulnerable girls on internet chat rooms and websites by implying that he ran a modelling agency. Blewett, of Twickenham, in Middlesex, admitted a number of charges, including sexual assault and others relating to making and possessing indecent child images.

Yesterday, at Leeds Crown Court, he was given an indeterminate public protection sentence - and must serve at least five-and-a-half years in jail.

He was also given a Sex Offenders Prevention Order and placed on the Sex Offenders Register for life.

After Blewett was sentenced, Detective Chief Inspector Neil Thewsey described him as a systematic and predatory sex offender, who posed a very serious risk to teenage girls throughout the country.

He urged parents to keep a watchful eye on their children's internet usage, adding: "It is extremely disturbing to think that the girls involved in the investigation were approached by this perverted man while sat in their own homes.

"It's a chilling thought, but it is one we must all wise-up to."