Several people were injured in clashes between police and demonstrators protesting against the upcoming Group of Seven (G7) summit in southern Germany.
A few thousand protesters gathered in the German resort town of Garmisch-Partenkirchen in a largely peaceful rally before small skirmishes broke out after bottles were thrown at police, who responded with pepper spray.
Several people, including police, reported eye injuries from the clashes.
The two-day G7 summit opens on June 7 at the Schloss Elmau Hotel near the Austrian border.
The G7 groups Germany, Britain, France, Italy, Japan, Canada, and the United States.
It was downsized last year from the G8 when Russia was expelled for its intervention in Ukraine.
The demonstration began with anarchists chanting slogans and anticapitalists denouncing a proposed trade deal between the European Union and the United States.
Police said 22,000 police are in southern Germany for the summit.
Protester spokesman Simon Ernst said demonstrators wanted to show their anger at the world leaders, referring to them as "the henchmen of bankers and corporations."