Police have voiced concern about self-styled "paedophile hunters" who set up undercover sting operations amid fears they are interfering in their work and potentially entrapping innocent people.
Kent Police said it has "significant concerns about people taking the law into their own hands" and the methods used following recent stings by vigilante groups.
The latest incident happened at Bluewater Shopping Centre near Dartford on Easter Sunday when a brawl erupted after a group called "The Hunted One" confronted a man suspected of grooming a teenage girl.
Live broadcasts of vigilantes confronting suspected groomers have been streamed on "The Hunted One" Facebook page. The group has since posted a statement saying it will no longer go live on stings.
Police have raised concerns about such vigilante operations and have publicly urged anyone with evidence of online grooming or knows a suspect is planning to meet a potential victim to contact them.
Chief Superintendent Thomas Richards, head of Kent Police's public protection unit, said evidence-gathering was a specialist job that takes time and skill to bring an offender to justice.
Mr Thomas said: "We do have significant concerns about people taking the law into their own hands and the methods they use, and in some cases acting outside of the law, and would strongly advise against getting involved in, or setting up activities to entrap those suspected of intending to commit offences.
"Although seemingly well-meaning, this can significantly hinder our work, compromise on-going investigations and negate months of investigative work.
"There is also the risk that it can potentially identify people who are completely innocent and mistakenly associate them with grooming offences."
Mr Thomas said the general public may also cause vulnerable people with mental health issues serious risk of harm, and that targeting dangerous offenders and keeping children safe was a "top priority" for police.
In a statement on its Facebook page, "The Hunted One" said: "After careful consideration and team discussions, we have decided that in moving forward that we will no longer be going live for the stings as we don't want cases and evidence ruined after all our hard work in collecting the information for a successful conviction.
"The safety of our team as well as the general public is paramount."