Rome's police commissioner has defended the behaviour of his force at last night's UEFA Champions League match between Manchester United and AS Roma.
Around 18 of the English club's supporters were injured in clashes with their Roma counterparts, and there have been complaints that many were hurt by riot police using batons.
However, Commissioner Achille Serra said the police reaction had been a justified response.
UEFA said it would launch an investigation into the trouble at Rome's Olympic Stadium.
UEFA spokesman William Gaillard said it was a sad night for football, but questioned possible confrontational crowd control methods by the Italian police.
The bulk of the injuries were received when supporters clashed with riot police after missiles were thrown during Manchester United's 2-1 defeat to the home side in the first leg quarter-final tie.
An estimated 4,000 Manchester United fans had travelled to the Italian capital.
