Internet Interceptors are one of several ‘paedophile hunter’ groups in Britain, with others including Dark Justice, The Hunted One and Paedo Hunters.
Members often pose as boys or girls in their early teens who lure an offender somewhere for a meeting after being sent explicit messages or videos.
There, the suspects are filmed with handheld cameras and mobile phones and told to explain themselves – with the messages and footage handed to police.
Last month Britain’s top police officer Cressida Dick said she had ‘significant concerns’ about vigilante paedophile hunters who pose as children online.
But the Met Police Commissioner admitted forces could not ignore the groups securing large numbers of convictions and being praised by the courts.
She said there were risks but that ‘on occasion’ officers could work with volunteer investigators who posted their stings online.
Police have used evidence from vigilantes in almost half of child grooming cases put forward for prosecution in recent months.
Groups such as Dark Justice have won huge online followings but police fear they could be putting themselves and suspects in danger.
Chief Constable Simon Bailey, who is responsible for tackling child abuse, said he is now losing the argument that the groups did more harm than good.
Last year, 114 police cases for ‘meeting a child following sexual grooming’ came from volunteer stings, a substantial rise from just 20 two years earlier.
Of the total number of prosecutions for this offence last year, 44 per cent were based on evidence from paedophile hunting gangs.
Police had threatened a clampdown on paedophile hunters after a disastrous sting broadcast online live from Bluewater shopping centre in Kent at Easter.
Vigilantes ambushed a man suspected of grooming what he thought was a 14-year-old girl, but ended up having to protect him, as shoppers watching the sting on Facebook Live raced across the centre and tried to attack him.