A man was rushed to hospital after being slashed across the face during a mass brawl before Millwall and Everton’s FA Cup match on Saturday.
The attack came as more than 50 rival fans were filmed laying into each other near Millwall’s home ground The Den in Southwark, London.
The footage – filmed from a balcony above the violence – has caused revulsion after being widely shared on social media.
The Metropolitan Police said no-one had yet been arrested following the trouble in the Hawkstone Road area but investigators were working to round up those involved.
Det Insp Darren Young, of the force’s South Central Command Unit, said: “The behaviour of those involved in this incident is nothing short of disgraceful and those involved can be certain we will be working to identify them.
“We are aware of the video circulating online, which has quite rightly elicited shock and disgust.”
Some critics online said officers on the ground had appeared slow to react to the trouble, which flared at 4.42pm ahead of a 5.30pm kick off. But, in a statement, the Met added they had “worked to separate the groups with support from the Mounted Branch and Dog Support Unit”.
It said the man who was slashed was in his 20s.
Meanwhile, more trouble was also reported when a coach taking Everton fans to the match – in which Millwall beat their Premier League opponents 3-2 thanks to a last-gasp winner – was attacked as it arrived in Southwark.
A relative of the bus driver told the Liverpool Echo: “The Millwall fans destroyed his bus.
“They were throwing bricks, bottles, anything they could get their hands on. He had to drive towards them to get away. All the windows on his bus are smashed.”
