The British government has voiced concern over the policing of Wednesday night's Champions League match between Roma and Manchester United.
"The scenes seen on TV are extremely worrying," Home Office Minister Vernon Coaker told the BBC in London.
"We need explanations for what happened, and the way the police reacted," Coaker said after Manchester Utd accused Italian police of "indiscriminately" hitting supporters after fans rained bottles of water on them.
Coaker said the government was eager to see reports from Italian and British police.
Top Swedish ex-ref Anders Frisk, who was at the Olympic Stadium, said the police had reacted "in a very aggressive way on one or two occasions".
Frisk, himself a victim of stadium violence in Rome in 2004 when he was left bleeding profusely from an object thrown from the crowd, also criticised police for allowing bottles and other objects into the stadium.
"It was a monumental error," he said.
Italian politicians reacted to the criticism by praising the police, while Sports Undersecretary Claudio Lolli said it would be a mistake to make a political incident out of the case.
Rome Prefect Achille Serra rejected allegations that the British fans were subjected to brutality during the match, which Man Utd lost 2-1.
Serra said the police were just doing their job. "In my opinion, the police's performance last night was correct".
There were also a number of clashes between Roma and United fans before the match. In total 18 people were injured, including one English man who is in hospital after being stabbed in the neck.
Serra played down the trouble. "It did not seem like a night of violence to me," he said.
"There were incidents before and after, but they certainly weren't serious".
He said three English fans were being held in connection to the trouble inside Rome's Olympic Stadium Wednesday and charges are being considered in one case.
The Italian media have stressed that many of the United supporters were drunk and rowdy.
The new head of the Italian Soccer Federation, Giancarlo Abete, also backed the police.
"I have great trust in the Italian police," he said.
"We owe a debt of gratitude to the forces of law and order, who have often had to pay a price that is too high".
In February a police officer was killed during rioting at a top-flight football match in Catania.
European soccer's governing body UEFA has opened an inquiry into Wednesday's violence.
Roma risks sanctions if UEFA judges crowd-control measures to have been inadequate, while Manchester United could be penalized if its fans are seen as the cause of the violence.
Before the match, Manchester United warned its followers to take precautions because they risked being attacked by hard-core 'ultra' Roma fans.
Rome Mayor Walter Veltroni complained that the warning would inflame the climate at the game.
