Dermot O'Leary now "knows" who took his wedding ring "thanks to Instagram", and hopes police will catch him.
The 'X Factor' presenter was left devastated last month when his bag, containing the band, was stolen from a gym in London, but he is now hopeful the thief will be stopped before he "does it to anyone else".
Speaking on 'The One Show', he said: "I had my locker raided while I was at an exercise class and he took my whole bag which contained my wedding ring, which I had taken off because it can get snagged and so forth, and my crucifix and my watch.
"Anyway, thanks to Instagram, we know who he is - I won't say his name because shenanigans are hopefully happening, so fingers crossed we catch him before he does it to anyone else."
At the time, Dermot shared a tweet from the City of Westminster Police calling for information if anyone recognised a picture of the guy.
It said: "Do you recognise this man? We wish to speak to him re theft of a bag from a gym in Mortimer Street W1 on 13 Aug. Items stolen include a wedding ring etched on inner side with '14/9/12 Team KO'. Pls call police on 101 ref 6195/21aug with any info about the man or the stolen ring (sic)."
Dermot retweeted the message and added: "Sadly this was my wedding ring & bag that was stolen. I'm sure I won't see them again, but I'd really like it if he didn't have the opportunity to steal yours. Please have a good look at the picture & if you recognise him call 101 ref 6195/21aug Dx @MPSWestminster @metpoliceuk (sic)."
The 47-year-old TV presenter has been married to Dee Koppang O'Leary, 41, since 2012, and the pair welcomed son Kasper together in June.
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