Bloodied and bruised fans arriving back from Manchester United's Champions League clash in Rome have spoken of their anger at Italian police.
Manchester United fans placed the blame on the Italian police
A number of United fans were taken to hospital, three with stab wounds, and some were arrested after clashes with police and Roma fans on Wednesday.
Some supporters arriving at Manchester Airport were bandaged and others had head wounds.
"The police were beyond control," said one eye-witness.
During the game, which Roma won 2-1, both sets of fans could be seen throwing missiles at each other.
Uefa has announced an investigation into the crowd trouble at the Stadio Olimpico, although United fans claimed it was Italian police who made the situation worse.
The Independent Manchester United Supporters Association (IMSA) led the condemnation of police for what it said were "hideous" attacks on fans.
Spokeswoman Carly Lyes said: "There was no need for the brutal level of violence they showed.
"The police charged in from all angles and were hitting people indiscriminately.
"They didn't care who got hurt. People were running all over the place trying to get away. It was chaos."
Businessman Stephen Fitzsimons, 53, from Stretford, Greater Manchester, was knifed in the groin as he made his way to the ground with three friends.
He was taken to hospital and twice underwent emergency surgery to control his bleeding.
Mr Fitzsimons, who hopes to be released from hospital on Saturday, told BBC Radio Manchester: "No police have been to see me... it's disgusting.
"The doctor said I was very lucky to be alive - I was 2cm away from being dead."
Some witnesses inside the ground spoke of terrified women and children running away from the police during one baton charge, while a disabled man was reportedly knocked out of his wheelchair.
BBC correspondent Christian Fraser, who was in the stadium, said trouble flared after Roma fans ran towards the perspex partition which separated the supporters.
He said Manchester United fans reacted and the police moved in with their batons in a response that was "at best robust and in some cases some officers went completely over the top".
The view was supported by Manchester United fan Debbie Robertson, from Rusholme, who told BBC Five Live that some police actually shielded her from their over-zealous colleagues.
"There was four or five police and they were coming towards me and my husband with the helmets and their batons," she said.
"We were sort of pinned against a perspex panel, so he (the officer) started to shield us and say, 'You'd better move somewhere else' but there wasn't really anywhere else to move to."
Another man, who arrived back in the arrivals lounge with dried blood still visible on a head wound, blamed the Roma fans for the trouble.
"The fans started throwing bottles and coins and the police just waded in with their truncheons," he said.
"They [the police] ill-treated us yet again."
Manchester United fans experienced problems with police during their last visit to Europe against Lille in Lens, France.
Prior to Wednesday night's game, Rome's mayor Walter Veltroni said United's warning to its fans about the violence threat was "dangerous because it risks creating a negative climate".
A statement released by Manchester United on Thursday said: "There were clearly some very disturbing scenes in the stadium last night.
"Until we have had chance to discuss the situation with the British Embassy in Rome and the Italian authorities and to understand the cause, it would be inappropriate to comment."
Rome's head of police, Achille Serra, insisted the police action was a "justified response", and said there would be no inquiry unless he were shown evidence of any alleged police brutality.
Italian Football Federation president Giancarlo Abete backed Mr Serra's comments: "The English press speak of heavy handed police? We owe gratitude to our law enforcers.
"I don't believe those who try to make games safe can be crucified in this manner."