Police are appealing for witnesses after a ticket inspector was attacked on a north-east train at the weekend.
The incident took place on the 10.27pm Aberdeen to Dundee service at about 10.40pm.
The culprit, a man in his mid-50s, grabbed the 35-year-old man around the throat, as the train approached Portlethen station.
The suspect, who is described as bald, with a heavy-build, and wearing a black jacket, black trousers, a blue shirt, and a black scarf, got off at Laurencekirk just before 11pm.
Officers have reviewed CCTV footage and the man responsible is seen being dropped off by the driver of a silver estate car around 1.30pm the same day.
British Transport Police has appealed for anyone with any information to contact 0800 40 50 40, or Crimestoppers on 0800 555 111.