A pervert has been jailed after he was duped by a vigilante group into believing he could have sex with a young girl.

Mark McKenna sent sordid messages and images to the fictional 11-year-old schoolgirl before arranging a meeting at Bluewater shopping centre in Greenhithe.

But the group called The Hunted One tipped off the police and officers pounced.

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The 38-year-old, of High Street, Northfleet, admitted arranging or facilitating the commission of a child sex offence.

Today, he was sentenced to five years in jail. His name will appear on the sex offenders' register for life and he will be barred from working with children or vulnerable adults.

Prosecutor Dominic Connolly said group member Andy Bradstock created a fictional profile of a girl called Lisa on Instagram in July this year.

With it was a photo of a young girl taken from the internet.

The profile was liked by McKenna and he started sending messages.

Over the next three-and-a-half weeks he sent images of male and female private parts.

Mr Connolly said the issue of age was plain from the outset as McKenna asked how old she was and was told "11 nearly 12".

VIDEO: Paedophile hunters confront McKenna at Bluewater

He told her he was a good deal older than her at 38.

He arranged to meet her at Bluewater on August 6, saying she would have to pose as his daughter.

He talked of kissing her and asked personal questions. He told her what he would like to do to her sexually.

"He messaged her to say he could get into trouble with the police and asked her to promise she wouldn't tell anyone," Mr Connolly told Maidstone Crown Court.

McKenna told her about sexual dreams he had about her.

He also said he had his house to himself as his girlfriend was away in London.

He promised to be gentle with her and to wear a condom.

On the morning they were to meet, he sent her a picture of an unopened condom packet.

Mr Bradstock went to Bluewater with four others and introduced himself to McKenna.
He replied: "I thought this would happen." He was then arrested.

Judge Philip Statman said there was a gap in the law as if it had been a real child, the maximum sentence would be life imprisonment.

The maximum for a "pseudo child" was 14 years after a trial.

"It is clear as clear can be this is rape of a child under 13," he said. "I have to apply guidelines which relate to sexual assault.

"There is a significant degree of planning and grooming and on the face of it targeting of a vulnerable child - a very serious matter indeed.

"Matters of this kind, horrendous as they are, ought properly to be left to the appropriate investigating police officers" - Judge Philip Statman

"He has got to be deprived of his liberty for a substantial time. It crosses the custody threshold by a mile."

Paul Jackson, defending, said McKenna was ashamed of what he had done.

After McKenna, who works for a cement company, was led to the cells, Judge Statman spoke of his concern about the involvement of vigilante groups in such offences.

“I am very mindful of the manner in which this particular case came to light, its gestation and how it was brought to the attention of the authorities,” he said.

“Offences of this kind need very careful investigation indeed. No member of the public can be fully aware of the scope of any police inquiry.

“Members of the public must be very careful indeed to ensure where matters such as this are canvassed through social media sites that no further offences are committed such that the individual involved in the original posting commits himself or herself a criminal offence.

“One sees clearly the danger that can arise into what subsequently happened in regard to the defendant and his family.”

McKenna lost his job, his partner left him after his arrest and he had to move home because he was vilified with hate mail and threats.

The judge added: “In my judgement - and I hope I am not speaking out of turn - matters of this kind, horrendous as they are, ought properly to be left to the appropriate investigating police officers who are there to safeguard the interests of the community as a whole.”

Ben Bleach, spokesman for The Hunted One, welcomed the sentence and said afterwards: “This particular case wouldn’t have gone to court if we hadn’t done what we did.

“We don’t want to interfere with the police. We speak to the police and we are getting information from the police to help do what we do better.

“Everything we do is properly done and on recommendations to ourselves. We believe we are doing the right thing. We are getting people behind bars and have a 100 per cent conviction rate.

“We are going to carry on and keep within the law and keep getting convictions.”

Judge Statman told McKenna: “In my judgement you had one intention in mind, and that was to have sexual intercourse with a child aged 11.

“To this end, you arranged to meet her at Bluewater shopping centre. When you arrived you became immediately aware you had been subjected to an internet sting to catch those with paedarast tendencies.

“The whole of your arrival was filmed. This was an act of facilitation, there being no real child upon which you could practice the abhorrent acts I have been told about.

“You have been subjected, perfectly understandably, to vilification in the community but more troubling, despite that which you have done, which is absolutely appalling, you have been subject to hate mail, death threats and the family home is one in which you can no longer live.”

The judge added he was satisfied McKenna would benefit from sex offender treatment, as he had “a long way to go” to have full understanding of what he had done.

After the hearing, an NSPCC spokesperson said: “McKenna thought he was meeting an 11-year-old girl. Although the child he was arranging to meet was not real, the danger he poses to young children is.

“While serving his sentence it is vital that he receives treatment to minimise the risk of him offending upon his release.

“Although he is now where he belongs, investigating crime is best left to the police. When the public take the law into their own hands it can run the risk of driving offenders underground, jeopardise on-going police work or result in innocent people being harassed.

“Anyone with concerns about children, or adults who pose a threat to them, can contact the NSPCC on 0808 800 5000 or email help@nspcc.org.uk.”