A 53-year-old man is in a critical condition after he was attacked outside Anfield before Liverpool’s Champions League semi-final match with Roma.
Two men, who are aged 25 and 26, and come from Rome, have been arrested on suspicion of attempted murder.
The victim suffered a head injury and is being treated in hospital, Merseyside Police said.
In a statement Liverpool said it was “shocked and appalled” and would be offering the victim “our full support”.
The attack happened outside the Albert pub in Walton Breck Road at about 19:35 BST.
Det Insp Paul Speight of Merseyside Police said: “Witnesses report that the victim was hit with a belt and then fell to the ground.
“His condition is currently described as critical and his next of kin have been informed.”
There were clashes between Liverpool and Roma supporters shortly before kick-off.
About 80 Roma fans are thought to have used a side road to reach an area populated by Liverpool supporters.
One supporter was seen motionless on the road and BBC Sport footage showed another fan carrying a hammer.
Trouble broke out behind the Kop End, with reports of Roma supporters attacking home fans.
BBC Sport news correspondent David Ornstein said the pre-match trouble started when a “group of Roma fans arrived via Venmore Street, burst on to Walton Breck Road and attacked, many using belts”.
He said a Liverpool fan was knocked to the floor and received lengthy medical treatment.
He added that there were “skirmishes, projectiles” and at least one person had “a hammer”.
Sunday Times football correspondent Jonathan Northcroft tweeted that the “attack was sudden”, adding that the “Roma group were chased down the street before police arrived”.
Police are appealing for anyone with video footage or information to contact them.
There was an increased police presence around the stadium after Manchester City’s team bus was attacked before their Champions League quarter-final with Liverpool earlier this month.
Liverpool were charged by European football’s governing body Uefa for throwing cans, bottles and flares at the bus.
Roma supporters have been involved in violent attacks against English fans before – several Tottenham supporters were injured in Rome in 2012.
Did you witness anything? Share your experiences by emailing.
You can also contact us in the following ways:
- Tweet: @BBC_HaveYourSay
- WhatsApp: +44 7555 173285
- Upload your pictures/video here
- Text an SMS or MMS to 61124 (UK) or +44 7624 800 100 (international)
- Please read our terms & conditions