A train guard who asked a passenger to put his pet on a lead was bitten by both the dog and the man.
The attack happened after the pet owner refused to put his animal on a leash, prompting the employee to tell him he could not board the train.
The vicious pooch then plunged its teeth into the guard's leg, before its owner punched him in the face and bit his ear.
He also grabbed the victim's head and threatened to rip his eye out in the brutal attack, which happened at around 3pm on February 17.
The passenger fled Upholland Station, near Wigan, after the assault, the Liverpool Echo reports.
Officers are currently investigating the assault at the station and today released an image in connection to their enquiries.
A spokesperson for British Transport Police said: "Do you know this man?
"Officers believe the man in the image may have information which could help their investigation.
"If you recognise him, or have any information, officers urge you to please contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 288 of 17/02/21.
"Alternatively, you can call Crimestoppers on 0800 555 111."
It comes just weeks after a three-year-old girl was mauled by a dog in a horrific attack in Birmingham.
The tot was walking with her mum and a two-year-old girl when they were set upon.
Footage showed the children screaming while being dragged and bitten by the aggressive animal.
The dog, believed to have escaped from a local business, was seized by officers following the attack.
West Midlands Police said the older child was rushed to hospital after sustaining serious injuries.
