Thugs shouted 'Manchester Manchester' at horrified onlookers after battering a man in a shop doorway in Liverpool city centre.
Mobile phone footage shows two men kicking and punching the man on Basnett Street in front of Christmas shoppers on Sunday, the Liverpool Echo reports.
At one point a group of onlookers tried to protect the victim from the men in the doorway of the food hall of Marks and Spencer.
The two attackers then walk away from the victim, but return to hurl abuse at him.
As a group of shoppers then scream at the men to go away one of them appears to chant 'Manchester Manchester ' at the crowd before walking off.
The violence appeared to flare after a verbal exchange between the victim and a group of three other men.
Police said they were called to the scene at around 5.40pm yesterday afternoon.
The force has now appealed for anyone with information about what happened to get in touch with them.
A police spokesperson said: "We were contacted at 5.40pm on Sunday 20 December following reports a male had been spat at and assaulted by three unknown males on Basnett Street in Liverpool city centre.
"The males made off before patrols arrived.
"The man suffered cuts and bruising to his head. Enquiries were carried out in the local area to trace the men.
"Anyone who can assist the investigation is asked to DM @MerPolCC or @CrimestoppersUK on 0800 555 111 quoting reference 20000772434."
