May 1, 2009, 21:48 GMT
Berlin - Hardline leftists vented rage at both neo-Nazis and riot police in numerous German cities Friday, with dozens of people injured in an annual ritual of May Day political rioting.
In the most savage violence of the day, 50 people including 29 police were hurt in a riot in the southern city of Ulm, where a crowd of several thousand people gathered to confront a parade by 1,000 far-rightists affiliated with the National Democratic Party (NPD).
Officers of the Ulm police on horseback, water cannon and tear-gas drove back stone-throwing leftists.
In the western city of Dortmund, it was the neo-Nazis, many of them masked and clad in black, who initiated the violence, using clubs and stones to attack a daytime rally of trade unionists. Police detained 200 rightists for identity checks.
In the capital Berlin, the worst violence occurred during the two nights, before and after May Day. On Thursday night there were 57 arrests after drunken leftists hurled stones and smashed cars.
Leftist youths formed up Friday night to volley cobblestones, bottles and petrol bombs at Berlin police armed with shields and clubs. Police dispersed a demonstration of 5,000 leftists as the mayhem got out of hand, and tried to catch the main offenders.
May Day, Europe's labour day, has evolved into the most violent day of Germany's political calendar, with clashes between the hard left and far right, who are fierce enemies, as well as attacks against the police, seen by the left as stooges of capitalism.
That set up the pattern of many of the clashes, with leftists trying to break through police cordons or hurling stones and bottles across the heads of the police to attack the neo-Nazis.
Senior political leaders in Germany have called for the NPD, a tiny party which is supported by many neo-Nazis, to be outlawed.
But courts have ruled that even neo-Nazis must be granted parade permits because of their constitutional free-speech rights.
Residents of Ulm, which has a significant Muslim minority, voiced outrage that judges had awarded the NPD a marching permit, although Ulm civic authorities had tried to ban the rightist parade for fear of violence.
'How could they allow a NPD demonstration here in the first place?' said Titiz Sevgi, 26.
Elsewhere in Germany, riot police arrested 40 rightists in Itzehoe, north-west of Hamburg, for refusing to disperse after 100 to 120 tried to stage a parade without any permit.
One of the biggest anti-NPD demonstrations, by 12,000 people, was in the northern city of Hanover, where a NPD parade was banned.
In Mainz, in the south-west, police arrested 50 leftists for throwing stones and smoke bombs at 100 parading rightists.
In a small northern town, Verden an der Aller, witnesses said 500 inflamed leftists fought a running battle with riot police.
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