A man suffered serious facial injuries after he was assaulted with a weapon at West Croydon Station.
British Transport Police (BTP) officers have issued images of two men following the assault at around 6.30pm on January 3.
The incident took place when two men prevented the victim from walking past them on the platform.
The victim tried to walk away and was threatened by one of the men, who then assaulted him with a weapon causing serious facial injuries.
Officers believe the pair in the images may have information that could help their investigation.
Anyone with information can contact BTP by texting 61016, or by calling 0800 40 50 40 quoting reference number 553 of January 3.
Alternatively, you can call Crimestoppers anonymously.