After over 2000 people protested on May 9th 2007 in Hamburg against a razzia in the Rote Flora (Sternschanze) the same morning police provoked a riot. It took place right in front of the Flora on the street Schulterblatt. 3 police officers were injured, several people were arrested.
The razzia in the morning was beacause of the suspicion that terror attacks were planned at that and 41 other places all over Germany in context with the G8-meeting in Heiligendamm in June 2007. (less info)