Craig Chapman (pictured) was messaging a 'youngster' and telling her how he wanted to meet her for sex

A couple created a fake teenage schoolgirl as 'bait' to catch a paedophile.

Katie and Neil Ivall put together a phoney Facebook profile for a 14-year-old girl they called 'Kerry.'

Craig Chapman was soon messaging the 'youngster' and telling her how he wanted to meet her for sex.

But when he turned up in a supermarket car park in Bedfordshire thinking he was meeting the schoolgirl for sex, he was met instead by Katie and Neil who filmed the encounter outside the store and called the police.

The couple's film of their 'sting' has now been put on YouTube and starts with overweight Chapman, 35, on his mobile phone by the store's entrance trying to call 'Kerry' to find out where she is.

He was, however, calling Katie, who - with husband Neil - was just feet away and moving in to expose the pervert.

The efforts of the husband and wife that day last October outside the Asda store in Dunstable resulted in Chapman being jailed for 16 months last month at Luton Crown Court.

The couple detained Chapman long enough for the police to get there and arrest him.

When shown the evidence they had gathered - the chat logs and sick online communications Chapman had instigated, describing in detail how he wanted to have sex with the girl who he knew to be just 14 - the police had a solid case against him.

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Katie and Neil Ivall (pictured) put together a phoney Facebook profile for a 14-year-old girl they called 'Kerry' to dupe the paedophile into meeting them

Chapman, from the Netherfield estate in Milton Keynes, then pleaded guilty to the offence of attempting to meet a female child under-16 when he appeared at the court on December 23.

Katie, 30, a receptionist and her builder husband Neil, 38 who live in Dunstable, have spoken of how they trapped Chapman, who at the time had a girlfriend.

They claim when he first made contact with their fake Facebook account he was told she was 15 years old. He was later informed she was in fact 14.

Chapman is confronted on camera by the Ivall's, before he tries to get away pretending that he was phoning a friend

'It had absolutely no effect on him whatsoever, ' said Katie.

'He was pushing to meet the girl. By now we had his picture so we knew what he looked like and eventually we had his phone number and he had the number for the girl which was the bait phone.'

On the day of the meeting - October 14 last year - it was arranged Chapman would drive into the car park of the Asda store in Dunstable.

Katie filmed the encounter that day as husband Neil made it clear to Chapman they knew what he was up to and informing him that the police were on their way

Katie said: 'As we were walking up to him by the entrance to the store we could see him on the phone and he was actually phoning the number he had for the girl he thought he was meeting for sex. He was ringing the phone in my hand.'

Katie filmed the encounter that day as husband Neil made it clear to Chapman they knew what he was up to and informing him that the police were on their way.

Chapman, clearly agitated by the filming, can be seen trying to get away from the camera, but the couple made sure his car was blocked in so escape was impossible.

He was then arrested.

Neil said: 'I am never aggressive, I am not out to physically hurt anyone, but to expose them.'

Katie added 'There is no entrapment involved in what we are doing. These men choose to talk like this to someone they believe is a young teenage girl. They ask for the meeting and it's only when they turn up that they realise they've been caught.'

The pair now say such is the scale of the problem that, had they the time, they could catch paedophiles on a daily basis.

They began hunting down the perverts in 2015 after discovering that four men had been attempting to groom a young female relative over the internet.

Their stings have taken them to Brighton, St Albans, Northampton and Nottingham, Norfolk and Rotherham and they are presently have a number of individuals in their 'sights.'

They say they would like to train others to form their own groups and hunt down the paedophiles with sting operations.

Bedfordshire Police have said in the past that people should never take the law into their own hands and risk putting cases in jeopardy so that genuine offenders escape being brought to justice.

But Katie and Neil say the they have had nothing but support from officers they have dealt with.

When Chapman appeared before Judge Michael Kay QC in December, he was jailed for 16 months and told that on his his release he will be on licence and must go on a sex offenders programme.