ONLINE paedophile-hunting has become a "cottage industry" it was claimed yesterday as a court heard how one predator was snared by three separate groups.

Mark Cardwell believed he was engaging in explicit instant messaging conversations via an app with four different girls, one aged just 12.

But in fact Cardwell, who was given an 18-month prison term after admitting charges of attempted grooming, had been taken in by false profiles posted by the groups and was talking to their adult members.

The 39-year-old said he had a van with a double bed and encouraged one of the ‘girls’ to lie to her parents about having a sleepover with friends in order that they could meet.

Cardwell, of Eldon Street, Darlington, also boasted: “I could teach you all sorts.”

His case was unusual as three different vigilante groups all engaged with Cardwell, using different fake profiles, with the members of one confronting him at his home, leading to his eventual arrest by police, and also alerting members of his family.

Robin Turton, prosecuting at Teesside Crown Court, described how the conversations involving Cardwell in September last year would start off innocuously, before he quickly began asking questions such as the whether the girl was wearing a bra and what breast size she was.

The chats would get more explicit with the defendant requesting naked pictures as well as sending them and encouraging the girls to commit sex acts.

Mr Turton said Cardwell, who also pleaded guilty to attempting to engage a child in sexual activity, arranged to meet one of the girls at a supermarket but never went through with it.

Cardwell told police he was in “self-destruct mode” and claimed to have no sexual interest in children.

His barrister Chris Baker said he had not fully come to terms with his motivation for wanting to contact children aged under 16.

He said Cardwell suffered from depression, low self-esteem and alcohol problems.

Mr Baker said: “It is clear that as a result of these groups he has lost his job, his house, his partner and his good name and he has only himself to blame.”

The judge, Recorder Amanda Rippon said she was familiar with such vigilante groups, but was not aware there were so many.

This led Mr Baker to remark: “I think they call it a cottage industry.”

Cardwell, who handed in a number of character references, was made subject to a lengthy sexual harm prevention order and will have to register as a sex offender.

There was sobbing in the public gallery as the defendant was jailed. Recorder Rippon said Cardwell’s persistence was one factor why a suspended prison was not appropriate as well as the number of offences.

Durham’s Police, Crime and Victims’ Commissioner Ron Hogg said: “Obviously I’m grateful for the evidence which has led to a conviction in this case, but I don’t think there’s really a place for vigilante groups in policing.

“Too many times they can undermine police enquiries. I know that the public feel confident to submit evidence to the police so that they can do their job thoroughly and professionally.”

Durham Police said it did not wish to comment.