A 43-year-old roofer who conducted a sexual affair with a 15-year-old girl over social media has been jailed for two years and eight months.

Mark McNeil met the girl at a family social gathering, said David Iles, prosecuting at Worcester Crown Court.

They kept in touch through text messages and pictures on mobile phones, which gradually became more and more explicit. "It was a classic case of sexual grooming," said Mr Iles.

McNeil, of Sutton Road, Kidderminster, pleaded guilty to causing a child to undertake sexual activity and to look at pornographic images. There were 48 indecent pictures at the least serious level.

Mr Iles said the offences came to light after the girl's father borrowed her phone and discovered sexual pictures.

The family immediately went to the police and McNeil was traced five weeks later. He was aware of her age but had told her she was sexy and asked her to pose for pictures.

He also sent her a naked picture of himself but later claimed to police that he had no interest in young girls.

McNeil, who had no previous convictions, realised he had been fooolish, said Gurdeep Garcha, mitigating. He submitted references for someone of good character and pointed out there had been no actual physical activity between an adult and a child.

But Judge Michael Cullum said that although McNeil had been decent and honest in previous aspects of his life he had asked the girl to adopt graphic sexual poses. He had a hold over the girl.

He ordered McNeil to register as a sex offender for life.