A SEX offender under investigation by police for sending lewd letters to his victims from prison has asked Tony Blair to help his campaign for law changes.

In a series of letters sent to The Northern Echo, Lawrence Petch criticises the police and justice system - and reveals he wrote to the Prime Minister to seek support for his cause.

The 54-year-old was jailed for six years in April last year after Teesside Crown Court heard how he made videos of naked teenage girls, showed them porn and made them dance naked for him.

The married truck driver posed as a photographer and plied his victims with drink before filming them in a bedroom labelled Sex Club.

Petch admitted having sexual activity with a child and forcing a child to carry out sex acts.

Durham Police and the Prison Service are investigating claims he sent some of his victims, who were aged between 12 and 16, rude letters from his cell in Acklington prison, in Northumberland.

In his first letter to The Northern Echo, Petch criticises reporting of the case for suggesting he engaged in sex acts with one of his victims - despite him later pleading guilty to the charge with one of the girls.

The sex offender also claims he did not realise how old some of his victims were.

He wrote: "Do not insinuate sexual activity took place when it did not.

"The 12-year-old posed in a crop top and a pair of shorts. She never took them off, nor did she ever pose without clothes or take part in any sexual activity with me.

"Some girls looked older and I didn't check enough."

In another letter, Petch, from Ferryhill, County Durham, criticises the police and claims they broke the computer he used to store indecent images.

Petch wrote: "I have complaints against Durham Police going back to 2000. Got sick of writing to them, tried writing to Tony Blair and got no reply."

He claims he tried to get compensation for his broken computer from the Criminal Injuries Board and also said he was finding it hard to come to terms with being sentenced to six years.

In other letters, he tells how he was attacked in his home by two men in a "reign of terror" because of his crimes and even brands one of the complainants in his case a liar.

He wrote: "The police are not bothered with the truth. Ever felt like people are against u? Just getting my head around six years. No real defence, so going to appeal. Did I get a fair deal?"

Petch has a string of sex convictions and was jailed in 1993 for indecently assaulting a 12-year-old girl