Officers are investigating the assault where a member of rail staff was punched by the man who had no ticket. At around 11.40am on 6 June, a Greater Anglia member of staff approached a man and asked to see his ticket. The man had no ticket and was issued with a penalty notice. When the train arrived into Peterborough station, the man became increasingly aggressive, before swinging a punch at the victim. A transport police spokesman said: "Fortunately the victim, a man in his forties, did not sustain any serious injuries. "Officers believe the man shown in these CCTV images may have information which could help them investigate." If you know who he is, contact BTP by sending a text to 61016 or by calling 0800 40 50 40 quoting reference 190048828. Or you can call Crimestoppers anonymously on 0800 555 111.