A man was left with a broken rib and head injuries after being set upon in an unprovoked attack at New Malden station.
British Transport Police have released a CCTV image of a group of people they would like to speak to in connection to the violent attack.
The victim, a 37-year-old station rail contractor, was due to begin work when he was assaulted at 1.30am on Saturday, May 17.
Police Constable Clive Thomas said: “The victim was approached by a group of two men and a woman who suddenly became aggressive, with the two men punching the victim repeatedly in an unprovoked attack.
“As a result of the incident the man sustained facial and head injuries as well as a broken rib.
“I am certain those in the images will have key information about the assault which, in different circumstances, could have left the victims with far more serious injuries.”
Anyone with information should call British Transport Police on 0800 40 50 40 or Crimestoppers anonymously on 0800 555 111 quoting reference number SSUB/B10 of 23/6/14.