Detectives investigating an attempted robbery at Leicester Square Underground station are today releasing this image in connection.
At 3.45am on Sunday 5 May, a man was walking through the station when another man grabbed and pulled at his necklace breaking it.
The victim was then pushed the floor, while the man fled the scene.
Detectives would like to speak to the man pictured as they believe he may have information that would help their investigation.
Anyone who recognises him is asked to contact British Transport Police by texting 61016 or by calling 0800 40 50 40, quoting reference 378 of 6 April.
You can also contact Crimestoppers anonymously on 0800 555 111.