Lazio could face UEFA punishment after crowd violence marred their Champions League qualifier against Dinamo Bucharest.
The tense 1-1 draw was overshadowed by reports of racist chants from some sections of the home support and clashes between fans which led to five Romanians being injured.
"We are waiting for referee and observer reports before we decide whether to launch disciplinary proceedings," a UEFA spokesman stated.
"Violence outside the ground unfortunately is a matter for police in Italy, but we had concerns about racism before the game and we take a no tolerance approach to that.
"There is no doubt that there is a violent history surrounding Lazio fans and we always seem to have problems."