Rome police announced the news on their website on Thursday. Francesco Ianari and Mauro Pinnelli, identified as fans of Roma, remain in jail after having initial charges of attempted homicide downgraded to aggravated wounding on Monday.
Seven people were injured in the attack, one with a knife before Tottenham's Europa League match against Lazio, Roma's rival club.
The stabbing victim, Ashley Mills, remains hospitalized after his right femoral artery was gashed.
Police said about 50 hooligans, their faces covered by motorcycle helmets and scarves, stormed the pub in Rome's Campo de' Fiori square where the Tottenham fans were drinking.
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