This is what I saw on May 1st, when my wife and I went out to see the parade that was organized by the Austrian Socialist Party (SPÖ) in Linz. Partly an exercise in reporting as well as in posting in a ZNet blog.
The beginning of the day saw a parade with marching firemen, workers in the local Voest Alpine, the Black community in Linz, sport clubs, etc. Many red flags (for the socialist party), many signs reivindicating the future, education, etc.
Those were the ones marching along Landstrasse (the main street). At the end of that street, some other groups were waiting to start marching along: the socialist left party (SLF); supporters of Abdullah Öcalan, according to the flags with his face; and nearly across the street, an anticapitalist group whose name I could not find learn from their signs. They did have one sign carried by black-hooded youngsters: "Against capitalism & against regressive anticapitalism". This was at about 10:00 am.
As well, a line of police officers which seemed to be there to prevent some or all from marching on the main street (the parade was more or less finished by that time). They closed in on the demonstrators and kept their positions. Later we would see some policemen on riot gear, but they did not intervene at all for as long as we were there.
The socialist and Öcalan supporters were allowed to pass the police line, the antifascists (for lack of a better name; I saw this written somewhere) were blocked but the police and did not attempt to pass. The other two groups stopped, came back, and stood on the other side of the line, chanting a few slogans on freedom and against the police. A while later, the police line doubled, and later the antifascist group was forcibly pushed away from the others.
Why were these demonstrators not allowed to march? Why were they pushed back (not the others)? I would love to know the official rationale behind this… it cannot be because of actual violence: I was about five meters away and saw no violent act before, during or after the police pushing, except for a girl who was for a few seconds lightly entangled with a policeman (in the group that was not touched by the police).
At about 11:00, both groups sat down on the street. A little bit later, the police starting taking out (non-forcibly) some quite young demonstrators from the antifascist group and taking pictures of them; I think I saw them holding paper sheets with their names as policemen photographed them.
Again, I would have liked to know why, but I did not dare ask the youngsters after they were finished (my German is quite bad, and they may not have been in the best of moods).
A bit later, we departed, leaving everyone in the same place.