The Italian newspaper La Repubblica has compared the scenes to "urban warfare". The violence is believed to have taken place at the Drunken Ship pub - images on La Repubblica's website appear to reveal the damage.
The Lazio fans were reportedly armed with knives, baseball bats, belts and knuckle dusters and they went on to "destroy" the venue. One witness told the paper: "We feared the worst."
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Travel industry chiefs have called for universal safety standards to be introduced across Europe, to help prevent future tragedies.
The tragic deaths of two children on a Thomas Cook Corfu holiday in 2006 could lead to a crisis of confidence for the travel industry.
Sunny spells for tomorrow, although the further we go into the weekend then we will see outbreaks of rain moving south eastwards