Warning: this report contains descriptions of explicit messages.
Teams of paedophile hunters from across the country are joining forces to form their own national federation, in an attempt to work more responsibly with law and order.
Sky News was given exclusive access to follow several teams from the Midlands and the north of England, who banded together to track down and confront a suspected sex offender.
Volunteers from four of the groups acted as decoys, posing as underage girls on internet chatrooms, to gather evidence on the man.
Assistant Chief Constable Dan Vajzovic is responsible for helping set national police policy around paedophile hunting groups.
He told Sky News: “There are occasions when activist groups have carried out investigations and handed over evidence to the police and that has resulted in dangerous paedophiles being locked up,” he said.
“However, our overall impression is that activist groups are not helpful to the policing operation for a range of reasons.
“Some of the activities we’ve seen them carry out have resulted in people with mental health issues and others with learning difficulties being targeted.
“People are sometimes not actually paedophiles.”
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