A London football fan who ended up in hospital after being attacked by hooded Ukrainians in Kiev said he was told the assault was a planned raid, and warned someone could get killed.
David Stone from Stanmore in north west London told The Sun he had been told the attackers "planned the raid on the bar to steal our England flags. They were getaway cars."
The history graduate was one of the three injured people who have now left hospital.
British police have urged England fans in Ukraine not to seek revenge for the attack, in which around 30 people armed with knives are said to have set upon the supporters in a central area of the capital.
Around 2,000 England fans are expected to attend tonight's World Cup qualifying game in Kiev's Olympic Stadium, and a win for England would move them to within touching distance of a place in next summer's finals in Brazil.
Mr Stone told the Sun: "These brutes could soon be up on a murder charge."
He added: "I woke in hospital. I don't even know how many stitches I had.
"I've been told these guys had planned the raid on the bar to steal our England flags. There were getaway cars."
Pictures of blood-spattered pavements quickly circulated on social media sites after the incident.
Witness Daniel Gover told the Daily Mirror it was a "random, unprovoked attack".
Anastasiya Nikolaeva told the Sun that watching the incident "was so horrible".
She said British fans were singing songs before a "crowd with flares" approached them.
She said the mob were "smashing bottles and breaking off branches of nearby trees".
"One victim was lying on the ground," she said.
Police had reported a relaxed atmosphere in the city where there were no problems last year despite a much larger number of supporters for two games in Euro 2012.
Rachel Barber, head of the UK police delegation in the Ukraine, said of Sunday's incident: ''We are aware of what happened and we will be going round most of the major bars, including this particular one, to make sure there are no problems.
''We would urge supporters to enjoy themselves but to do so without upsetting anybody.
''I am pleased to say that currently the atmosphere in the town is good, so in that sense what happened last night was out of the blue.
''Sometimes there can be an element of bravado on social media and you can never legislate for something happening but hopefully the England fans will just have a good time in what is a fantastic city.''
A Foreign Office spokeswoman said: ''We are aware of incidents in Kiev involving British nationals. We are providing consular assistance.''