Greek riots

The violence brought downtown Athens to a standstill, and erupted after some 300 members of neo-Nazi group Chryssi Avghi, or Golden Dawn, gathered for a protest. They claimed they wanted to liberate Athens and Greece from what they described as "hordes of illegal immigrants".

They unrolled a huge Greek flag and banners calling for the "departure of foreigners from Greece" and claiming "foreigners equal crime".

At the city's old Court of Appeal, where 500 immigrants have been squatting for several weeks, dozens of protesters hurled rocks and firecrackers at the eight-story building which has no electricity, running water or sanitation. Others shouted "Out of Greece" and "Leave Greece for the Greeks".

The squatters retaliated by throwing stones from the upper floors of the building and riot police were called to break up the clashes.

Counter-protest triggers further violence

Further fighting broke out between the neo-Nazis and a group of anarchists, as police struggled to separate the two sides.

In a counter-protest, the young anarchists protested against the extremists' demonstration, which they termed a "racist gathering". They set fire to garbage cans and cars. There were no injuries but at least two people were arrested.

The clashes followed a call from rights groups for the Greek government to abandon a planned police operation, that would see the immigrants expelled from the old courthouse. They suggested instead the building be cleaned until appropriate alternative lodging can be found.

Greece has been rocked by a wave of violence since December, when the fatal police shooting of a teenager triggered the country's worst riots in decades.