More than 44 per cent (114 of 259) cases of the crime of meeting a child following sexual grooming used this evidence in 2016, compared to 20 out of 176 cases in 2014 (11.3 per cent).

Chief Constable Simon Bailey, the national lead for child protection at the National Police Chiefs' Council, told the BBC: "(These) vigilante groups are putting the lives of children at risk.

"I'm not going to condone these groups and I would encourage them all to stop, but I recognise that I am not winning that conversation."

When asked whether police could work with vigilantes, he said: "I think that's something we're going to have to potentially have to look at, yes, but it comes with some real complexity."

Tyneside-based duo Dark Justice claim on their website to have helped apprehend 104 sex crime suspects, leading to 50 convictions.