Beyond shouting slogans, police spokesman Roman Hahslinger said Tuesday that some suspects flashed the Hitler salute or other gestures associated with the Nazis during last month's demonstration, which was modeled after Germany's PEGIDA movement.
As many as 25,000 supporters of PEGIDA, or Patriotic Europeans against the Islamization of the West, turned out in German cities last year. In Vienna, the demonstration attracted about 200 people.
Police say the suspects, seen on photos and videos, have yet to be identified.
Austrian law prohibits gestures, words and actions linked to the Nazi regime. A conviction can carry a prison sentence of up to 10 years.
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