A man has been arrested in Merton on suspicion of grooming offences.
Exposure Central produced a 43-minute video from Church Path on January 10, showing a group confronting a man.
During the footage it is claimed a man had been contacting a 14-year-old via phone after getting the child's details online.
Police officers can be seen arriving to arrest the man in the video and searching him.
A spokesman for the Met Police said: “We were called at around 9.15pm to reports of a man being apprehended on Church Path in Merton following contact with a child online.
“There was no child online, members of the public had been in contact with the man over the internet.
“Officers attended and arrested the man, aged in his 40s, on suspicion of grooming offences. He was taken to a west London police station where he remains in custody.
“Enquiries continue.”
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