A judge has condemned police for only cautioning a convicted sex offender who breached a court order before going on to abuse more children.

Craig Mason, 21, was given a sexual offences prevention order in December 2004 for having sex with underage girls.

But after breaching the order he was only given a caution by police and was allowed to remain free.

Sex offender Mason went on to breach the order a further three times between April 2005 and March 2007 and commit four sexual acts against children.

Judge Charles Wide, sitting at Northampton Crown Court [last week - 1/5/09], criticised police for letting Mason off with a caution.

He said: "I'm very concerned that someone was cautioned in these circumstances and at the same time he was committing these serious offences."

Mason admitted four charges of sexual acts against children, including two of intercourse, as well as three other breaches of the prevention order.

He pleaded guilty to two counts of a sexual act with a child under 16 and admitted two more charges of a sexual act with a child.

He denied two charges of sexual touching.

He breached his sexual offences prevention order on three occasions between April 30 2005 and March 01 2007, between October 28 2005 and July 1 2006, and between January 31 2006 and April 1 2006.

The court heard that Mason, of Irthlingborough, Northants, had previous convictions for three indecent assaults and two of sexual intercourse with underage girls.

A Northamptonshire Police spokesman said they would not comment on ongoing cases.

A spokeswoman for the Crown Prosecution Service said: "If the police issued him with a caution for the initial breach that matter would have been considered dealt with."

Mason was released on bail and the case adjourned for sentencing until May 28.

Michele Elliott, director of children's charity Kidscape, said: "The reality is that you might as well spit into the wind when it comes to cautioning sex offenders.

"If there are no consequences for their actions there is no deterrent and these people will re-offend, which leaves vulnerable children at risk."

Sandra Brown, founder of children's campaign group The Moira Anderson Foundation, said: "It really underlines the need for monitoring arrangements to be absolutely clear cut.

"I do not think we can afford to err on the side of laxity at all.

"Unfortunately there are still examples of occasional leniency that have horrifying repercussions."