A former school governor is beginning a four year prison sentence for indecently assaulting a 13-year-old girl.

Peter Cook, 44, from Neyland in Pembrokeshire, west Wales, was described at Swansea Crown Court as a "fixated paedophile".

The former medical researcher pleaded guilty to one charge of indecent assault and six charges of possessing indecent photographs.

The assault charge involved a teenage girl, to whom he was not related.

The court heard that the girl had been invited to Cook's house, where the assault took place.

It was a well planned sexual attack, which the defendant had arranged to be filmed.

And that video of the assault was to form the basis of the evidence against him.

The court was told that Cook was arrested at his home after his victim complained about the assault to a schoolfriend.

Photograph collection

The police search of his house took three days, and recovered 200 videos and a collection of photographs featuring child pornography, much of which had been downloaded from the internet.

Passing sentence, Judge Michael Burr described Cook's victim as a welcome guest in his home, who had been assaulted in the most appalling way.

He said the defendant had an obsession with young children and that his behaviour was not to be tolerated in a decent society.

Cook's name has been added to the sex offenders register.