Manchester United have condemned the Italian police following the violence in the Champions League tie with Roma at the Stadio Olimpico on Wednesday.
Riot police charged fans at the Stadio Olimpico
"In what the club views as a serious over-reaction, local police handed out indiscriminate beatings to United supporters," said a United statement.
"The disturbing scenes shocked everyone at Old Trafford."
Uefa has launched an investigation, while United want supporters to send in witness statements.
The Home Office have confirmed they will gather information from all relevant sources before deciding whether to approach Uefa about their concerns.
Italian Football Federation president Giancarlo Abete praised the action of police.
"We owe gratitude to our law enforcers and I don't believe those who try to make games safe can be crucified in this manner," he said.
We are definitely in favour of soft policing
Uefa spokesman William Gaillard
Uefa has confirmed it has opened an investigation into the shocking scenes.
A statement said: "Uefa is currently gathering evidence and will be studying the official reports of the referee, delegate and security officer in detail before announcing any further action."
The investigation could lead to disciplinary action for both United and Roma.
Roma could be charged if they are judged to have failed in their security arrangements, while United could be in trouble if their fans are found to have a played a significant role in provoking the police's reaction.
Earlier in the season, United were fined £6,300 for the poor behaviour of their supporters in the away leg against Lille in Lens.
The trouble flared when rival fans surged towards a barrier separating them and missiles were thrown.
Baton-wielding riot police were seen repeatedly striking United supporters, including at least two as they lay on the floor.
Uefa spokesman William Gaillard said Uefa has little control over the police.
"Italian law says police are responsible for public order inside stadiums. Stadia in Italy are municipal stadiums, they are not the property of the club," he told BBC Radio Five Live.
"We are definitely in favour of soft policing, which is clearly the use of stewards who we know can handle a difficult situation probably better than riot police.
"We are subject to the law so we cannot tell the Italians and other countries where police are in charge of public order in stadia not to enter stadia.
"We are just a football authority not a law and order authority."
Both Manchester United and the BBC are interested to hear eye witness reports from people inside or outside the stadium.
For Manchester United, contact: Roma Inquiry, Manchester United FC, Sir Matt Busby Way, Manchester, M14 0RA or e-mail firstname.lastname@example.org