Pilkington, a Conservative councillor, was cautioned by police after child pornography was found on his computer, causing him to resign from the council.

Pilkington, aged 38, who resigned as Conservative councillor for Stratford on Avon District Council ward The Vale of the Red Horse on Wednesday, said he had no idea how the images came to be on his computer, was cautioned by police after child pornography was found on his computer.

According to a spokesman for Stratford council, he complained in July that his council-owned computer had crashed. An IT support officer found images of child pornography when attempting to fix the computer and immediately reported the matter to the police. "I didn't know they were on the computer" said Pilkington. "It was full of rubbish, it was all bunged up with stuff." "I was getting a lot of e-mails and I didn't know where they were coming from." "I thought I had deleted them all but obviously I hadn't deleted all of them." He said he did not use the Internet on the computer.

Pilkington, who was single at the time and lived in Shipston-on-Stour, Warwickshire, initially denied being cautioned by the police. "I was interviewed by the police after I came back from holiday a week last Friday but that is as much as I know." He said. After being read the Warwickshire Police statement, that he had been cautioned, Pilkington said: "Well, I suppose I must have been."

Pilkington had been a councillor for the ward since 1999 and was chairman of corporate services on the council. He listed his political activities as Young Conservative chairman, chairman of Shipston division Conservative Association and deputy chairman of Tysoe Conservative branch.

Warwickshire Police said a man had signed the Sex Offenders Register after being cautioned for two counts of possessing indecent images of children.A Warickshire Police spokeswoman said: "I can confirm a 38 year-old man from Shipston was cautioned on August 2, on two counts of possessing indecent images of children. He was required to register himself on the Sex Offenders Register, which he has done."