An English fan has been stabbed and is in a serious condition in hospital after a gang of 50 armed Italian hooligans stormed a bar and attacked a group of Tottenham supporters.
The Spurs fans were drinking in Rome's Drunken Ship pub ahead of Thursday evening's Europa League clash with Lazio when trouble flared.
The attackers - thought to belong to the club's notorious hooligans the Ultras - stormed the bar armed with knuckle dusters, baseball bats and broken bottles at 1am.
Several English supporters were injured along with a Californian and a Bangladeshi. The brutal attack left the famous cobbled square of Campo de Fiori covered in blood.
Italian sources said Spurs fan Ashley Mills, born in 1987 and believed to have been stabbed, was seriously injured and was being treated at the city's San Camillo Hospital. Other injured fans were named as Dave Lesley, Stephen Tierney and Christopher Allen.
Pub landlord Marco Manzi described the moment when the Spurs fans - who were "well behaved" and "drinking and singing quietly" - were attacked. "The bar was full of about 30 English supporters at 1am. Most of them were aged between 40 and 50 and they were well-behaved.
"Then arrived what I presume were Italian supporters wearing scooter helmets with their faces covered with scarves carrying stones and rocks. They arrived in the pub and they attacked the English supporters.The whole operation from start to finish was over in around 10 minutes. Most of the fans left and the police arrived."
Rome police confirmed up to 50 assailants launched the assault which had drinkers scrambling from the popular night-spot - situated in one of the capital's most colourful and renowned squares.
A spokesman for Tottenham Hotspur said: "We understand from local police that nine of our supporters suffered injuries last night following an incident in the city centre. Three of these supporters were taken to hospital for further treatment. We continue to seek further information and are liaising with both Italian and UK police on this matter."
A spokesman for the Foreign and Commonwealth Office said security would be increased for the game: "We are aware of a serious incident involving British nationals in Rome. We are in contact with the Italian authorities and the Italian police, who are investigating the incident and have confirmed there will be increased security measures for the game this evening. We have been in contact with one British national and have been updated by hospitals on the conditions of all the others, some of whom have already been released."