Online child predator-shaming group POPSquad has recorded more than 130 stings and claims to have been involved in 14 arrests, which NBC News has verified, though not all were charged with crimes related to videos of the encounters.
It's one of dozens of such groups that have sprung up online, especially in the last year, mining similar territory to the NBC News "Dateline" show "To Catch a Predator," according to an NBC News review of the groups on Facebook.
"In this field, sex crimes, no one can hold a candle to me. And that's a problem," said Shane Erdmann, also known as "Incognito," who founded POPSquad in Connecticut two years ago.
The groups' stings sometimes end with a potential child predator in police custody. But many law enforcement officers consider them dangerous vigilantes.
In one case from October, a 20-year-old gay man from Torrington, Connecticut, went home after being confronted by Erdman at a sting and hanged himself. Erdmann declined to comment on video of the encounter, posted to Facebook and later removed, and threatened to sue NBC News when asked follow-up questions.
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