An investigation is underway to find a man and woman after two members of staff were spat at on a train in Doncaster.
The incident happened when the members of staff challenged a man and woman who went into a toilet cubicle together when a train was stationary at platform six at Doncaster Station on Thursday, March 16.
British Transport Police said the couple became abusive when challenged by members of staff.
A CCTV image has been released of a man and woman believed to hold vital information about the incident.
Anyone with information should call 0800 40 50 40 or text information to 61016, quoting reference number 289 16/3.