Photo Gallery The Next Potential Flashpoints
People living in Europe's biggest cities are familiar with images like this one. The photo from 2009 shows a young man lobbing a stone in Hamburg's central Schanzenviertel district. Each year on May 1, anarchists and extremists take part in demonstrations that generally escalate into property damage and sometimes injuries.
This week thousands of marauding youths roamed through London and other English cities, setting fires, looting stores and clashing with police. They had no political agenda -- even if unemployment and poverty may have been causes of the riots.
Fire departments struggled to keep up with the fires set during the riots.
The destruction, shown here on Tuesday morning in London's Croydon district, was extensive.
During the day, the situation seemed to calm down.
A man looks through a ruined storefront window at a supermarket.
Rioters in Hamburg and Berlin on May 1 also lack any kind of coherent message.
In the Greek capital of Greece, on the other hand, people are outraged over their country's financial crisis and the subsequent austerity measures. In recent months demonstrators have clashed with police repeatedly.
In Italy, football hooligans are often involved in civil unrest. In this 2010 shot of Rome, hundreds of people demonstrate against cuts to education spending and Prime Minister Silvio Berlusconi's policies.
While the situation on Spain's streets may not be quiet, demonstrations against the government and high unemployment have remained peaceful. For weeks, tens of thousands of student demonstraters camped out in central Madrid to protest spending cuts and demand a greater say in government decisions.
In 2005, riots hit up to 200 French communities after two teenagers died during a police pursuit.
