More than 50 fans were arrested in separate incidents of violence prior to UEFA Cup matches in Austria and the Netherlands on Thursday.
At least 13 were arrested when about 150 Rapid Vienna and Anderlecht fans clashed at the Westbahnhof train station in Vienna. No injuries were immediately reported, but police said brawling fans blocked two tramway lines and that broken glass was strewn across one of Vienna's main shopping avenues.
Police said witnesses reported seeing some fans vandalize small outdoor drinking establishments and smash car mirrors.
Rowdy groups of 20-30 bare-chested fans were seen drinking beer Thursday morning, and there was a heavy police presence around Hanappi Stadium.
Police said fans of the two rivals had clashed last month in Belgium, and that hooligans were expected to stage a rematch in Vienna.
In Amsterdam, two police officers were wounded when hooligans identified as Ajax supporters threw bottles at them - resulting in 38 arrests prior to the game against Dynamo Zagreb, Dutch national broadcaster NOS TV reported.
The report added that Amsterdam police had anticipated retaliatory attacks on Dynamo fans following accounts that Ajax supporters had been "abused" in the first leg tie on Sept. 20.
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