A passenger on a train from Chesterfield to Wakefield Westgate was racially abused by two men, police say.
Two men got on the train at Chesterfield, on the Plymouth to Glasgow service, at about 15:30 on 30 November.
They racially abused a man and threatened him with violence.
Another passenger tried to help, but was also abused.
The suspects left at Wakefield Westgate.
Officers would like to speak to the men in the image in connection with the incident.