A group of RSF Firm ultras of La Liga side Real Sociedad attacked a bus of Roma fans before a Europa League meeting at the Anoeta Stadium on Thursday.
One day after the violent clashes between ultras and Police in Naples, there are more incidents involving supporters of Serie A clubs around Europe.
A video shows a bus of Giallorossi supporters attacked by many hooded people. Reports in Italy and Spain claim they belong to the Real Sociedad ultras group RSF Firm.
Some Roma fans inside the bus reportedly wanted to get off to face their opponents, but the Guardia Civil quickly arrived at the spot.
According to ForzRoma.info, at least two Roma fans were arrested, plus others of Real Sociedad.