Left-wing activists in Vienna have clashed with police who stopped them from approaching far-right demonstrators.
The right wingers were protesting against an exhibition that documents atrocities committed by German soldiers during the Second World War.
Throwing bricks, wooden sticks and paint bombs, several of about 3,800 left-wing demonstrators attempted to push their way through barricades sealing Heroes' Square.
They were held back by about 800 police along with water canons.
A spokeswoman said 38 police officers and 18 protesters were injured in the fray, with one of the officers seriously injured. Police arrested four protesters and plan to bring criminal charges against them for attacking the police.
The leftists tried to approach about 120 far-right activists who were protesting a recently opened exhibition on Germany's wartime army, which they oppose for depicting German soldiers as war criminals.
The far-right demonstrators, who say the soldiers were heroes, held their demonstration in the central square where Adolf Hitler addressed an enthusiastic crowd in 1938 immediately after annexing Austria.
Protesters held banners saying "despite the lies, we know the truth," and: "grandfather, we thank you," as well as photographs of soldiers with the words "hero" and "thank you" appearing under some of them.
At the leftist rally, demonstrators carried banners reading "give no inch to the fascists" and "solidarity with the victims of anti-Semitism".
PA