Roma and Lazio fans have clashed in the capital just hours before the two meet at Stadio Olimpico.
Reports suggest that the violence erupted on the Ponte Milvio in Rome between two groups of supporters, with news agency Calcio 24 claiming that a Giallorossi fan was stabbed in the buttocks.
Police have now been called to the area.
The Biancocelest host Aurelio Andreazzoli's men this evening in the Derby della Capitale.
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