UEFA recently fined Legia Warsaw 30,000 Euros because the club's fans displayed racist behavior during a qualifying round game. UEFA also forced the team to close down its north stand in the stadium because that section houses the team's rowdiest fans.
"Prior to the second-leg match against Steaua, Legia supporters choreographed a large display in the club's colors that spelled out "UEFA Ultra Extreme Fanatical Atmosphere" with a heart as a background. It then disintegrated into an orgy of flares that told the administrative body exactly how they felt about the sanctions."
(GIF via KickTV)