A grainy film shows the shops of Bluewater at the moment a 30-year-old man walks into the frame, allegedly believing he was meeting a 13-year-old girl.

More than 1,500 people who’ve watched the clip see three people confront him accusing him of online grooming, before police arrive.

Footage like this is becoming more common and is often shot after so-called ‘paedophile hunters’ pose as a vulnerable, underage child using an app or social media and wait for an individual to start a sexual conversation.

They encourage a meeting to publicly expose their target.

The KM approached the Hunted One, a group claiming to be behind the Bluewater sting.

An anonymous member revealed it is formed of 10 people, all parents, and said their work had led to several convictions.

The parent told us: “To date naming and shaming hasn’t had a negative effect on any trial nor has it been frowned upon by any judge. If anything, we are praised for our work.”

They said they used all public resources legally available such as the electoral roll and ensure all evidence is heavily documented and ‘100% water-tight.’

“Of course, it has a ripple effect with the person’s family getting hurt but this is caused by the perpetrator, their sole actions.

“We display the chatlogs, pixellated photos and the video of the ‘meet.’

“This is all for public viewing, so parents/guardians can make up their own minds.”

Reports of child sex abuse have more than tripled in Kent over the last four years, from 76 in 2012-13 to 282 in 2015-16.

Police say this shows more people are reporting concerns.

DS David Shipley of the paedophile online investigation team said: “I would strongly discourage people from taking the law into their own hands to avoid them being put in any danger.

“Revealing the identity of alleged paedophiles, often on the basis of little information, frequently leads to suspects being threatened and diverts significant police resources into protecting them.

“Due to the sensitive and often covert nature of our operations in this arena, we don’t routinely publicise they are taking place.”

But The Hunted One group member said: “The authorities protect the paedophile’s identity against the child. Acting on our moral code we protect the children, not the paedophile.”

The NSPCC also cautioned against paedophile hunting. A spokesman said: “Investigating crime is best left to the police.

“When the public take the law into their own hands it can also jeopardise ongoing police work or result in innocent people being harassed.”

In the Midlands a man had to move 100 miles away from his family after losing everything following a paedophile-hunting sting, which publicly exposed him. Police reviewed the evidence and concluded there was no case.

One man who thinks he could help the groups is Nick Kenward, from Maidstone, whose firm, Galleywell Security, offers advice on detaining someone.

The 49-year-old said: “If detaining someone, they have to let them know exactly what they’re doing and have to write contemporaneous notes as part of the evidence.”

He added: “The notion of innocent until proven guilty is very much intact throughout the legal system.”

If you think a child is at immediate risk of harm call 999.

The man on the Bluewater footage has been arrested on suspicion of grooming and bailed by police until December 9.

More information available at the Child Exploitation and Online Protection Centre (CEOP) by visiting www.ceop.police.uk