A PERVERT who groomed a school boy for years before offering to pay him for naked pictures to him on Snapchat has been jailed for four years.

Arron Lyons, of Forgeway, Banbury, dramatically changed his plea mid-way through his trial at Oxford Crown Court last week.

The 33-year old admitted one count of causing sexual exploitation of a child, one count of inciting a child to engage in sexual activity and three counts of making indecent photographs of children.

During the trial the court heard that Lyons had befriended the then 12-year-old boy at a BMX park before lending him money on numerous occasions to pay for food and alcohol.

Over time Lyons began offering to pay the boy to send him sexually-explicit photos through the social media application.

He was also found to have hundreds of indecent images and videos of children, including those sent by the youngster, on his phone and laptop.

At his sentencing hearing on Tuesday Judge Maria Lamb - who presided over the short-lived trial, said that Lyons had led a 'systematic and calculated pursuit' of his victim.

She said: "You progressed by what was a concerted and classic grooming technique, you gave him all the things that young boys covet."

In mitigation his defence barrister told the court that his client intended to do good work after release from prison and planned to complete a charity cycle ride across the UK.

Lyons was ultimately given a four-year jail term - made up of two years for causing sexual exploitation of a child to run consecutive to one year for inciting a child to engage in sexual activity and a further one-year consecutive jail term for all three counts of making indecent images.

He will also be subject to a sexual harm prevention order and need to sign the sex offenders registry for life, as well as pay a victim surcharge.