A MAN who attempted to groom a teenage girl for his own 'obsessed' sexual gratification has been jailed.

David Sadler sent a number of explicit Facebook messages to the young girl before moving onto using WhatsApp to encourage her to engage in sexual activity with him.

When the 37-year-old was arrested at his home police officers discovered a small number of indecent images of his target, which were secured in a password protected digital file, as well as extreme pornography.

Harry Hadfield, prosecuting, told Teesside Crown Court that Sadler was caught by the National Crime Agency after his illicit sexual messages were discovered in April last year.

"The messages in this case are extreme," he said. "The one on April 7 was the most graphic. He arranged to engage in sexual activity with the teenager and incite her to perform sexual activity."

In a victim impact statement, the teenager said the offences, carried out over a three-week period, had left her feeling upset and constantly crying.

Reading out the statement, Mr Hadfield said: "It says she has been left feeling on edge at school in case people find out and ask her about it."

During a police interview, the defendant claimed that the messages were 'fantasy' and he had no sexual interest in children.

The court heard that the defendant had made several attempts on his life while on remand awaiting his sentence.

Sadler, of Milfoil Close, Marton, Middlesbrough, pleaded guilty to engaging in sexual activity with a teenage girl, inciting a child to engage in sexual activity, having sexual communication with a girl under the age of 16, possession of indecent images of a girl and possession of extreme pornography.

In mitigation, Nigel Soppitt said the charges had 'devastated' his client's life as it was now in 'tatters' after quitting his job and moving back in with his parents.

He said Sadler was also aware of the harm he had caused.

Judge Paul Watson QC jailed Sadler for three years and four months for the offences.

He said: "You were obsessed with her in March and April, you were exchanging messages with her of an explicit and sexual nature to encourage her to engage in sexual activity and have sex with you."

Sadler was also issued with an indefinite sexual harm prevention order and ordered to sign on the sex offenders' register.