Riot policemen assist a colleague whose clothing caught fire after being hit by a petrol bomb during rioting in central Athens, Oct. 20, 2011.

A man shouts while helping an injured demonstrator during clashes between communists and black-clad youths near the Parliament building in Syntagma (Constitution) square in Athens October 20, 2011. Angry protesters vowed to bring Greece to a standstill on Thursday while disgruntled lawmakers vote on the details of a deeply unpopular austerity package needed to stave off bankruptcy.

A protester sits bleeding during clashes between communists and black-clad youths near the Parliament building in Syntagma (Constitution) square in Athens October 20, 2011.

Communists, left, clash with black-clad youths near the Parliament building in Syntagma (Constitution) square in Athens October 20, 2011.

Riot police detains a demonstrator during clashes in Athens, Greece, 05 October 2011. Civil Servants' Supreme Administrative Council (ADEDY) and General Confederation of Workers of Greece (GSEE), Greece's two largest umbrella federations representing the public and private sector staged a 24-hour nationwide strike protesting against the ongoing austerity measures taken by the Greek government.

Policemen take their positions around the parliament during a protest in Athens' Syntagma (Constitution) square October 5, 2011. Police fired tear gas at stone-throwing youths in central Athens Wednesday, where thousands of striking state sector workers marched against cuts the government says are needed to save the nation from bankruptcy.

A protester clashes with a policeman during an anti-austerity rally in Athens' Syntagma (Constitution) square October 5, 2011. Police fired tear gas at stone-throwing youths in central Athens Wednesday, where thousands of striking state sector workers marched against cuts the government says are needed to save the nation from bankruptcy.

Anti riot policemen clash with demonstrators during a protest rally marking the 24-hour general strike on October 5, 2011. More than 30,000 public sector workers demonstrated in Greece today in a strike against deeper austerity cuts that shut down courts, schools and transport, including air traffic.

Protestors push a high fence blocking the entrance to the Greek Parliament during a demonstration in central Athens, Greece, 05 October 2011. Civil Servants' Supreme Administrative Council (ADEDY) and General Confederation of Workers of Greece (GSEE), Greece's two largest umbrella federations representing the public and private sector staged a 24-hour nationwide strike protesting against the ongoing austerity measures taken by the Greek government.

A protester wearing a gas mask walks beside a burning van during violent protests against austerity measures in Athens onTuesday, June 28. With Greece teetering on the brink of bankruptcy, parliament is due to vote this week on a package of spending cuts, tax increases and privatisations agreed as part of a massive bailout aimed at averting the euro zone's first default.

A protestor throws a broken piece of furniture to riot police during clashes at central Athens Syntagma square by the Greek Parliament on Tuesday. Workers staged a 48-hour general strike against the bankruptcy-threatened government which is desperately trying to push through sweeping austerity cuts. As parliament votes on the drastic belt-tightening measures to unlock 12 billion euros ($17 billion) of blocked funds from the EU and IMF, unions have called on Greeks facing hefty tax hikes to stage mass demonstrations.

A demonstrator jumps to attempt to break a window displaying an image of an ancient greek galley during protests against austerity measures in Athens on Tuesday.

People sit in front of a closed bank in Athens on June 28 during a general strike. Greece ground to a halt on June 28 as a 48-hour general strike began to bite against the bankruptcy-threatened government which is desperately trying to push through sweeping austerity cuts.

Communist-affiliated unionists rally toward the Greek parliament in Athens on June 28.

Riot police stand guard near the Greek parliament in Athens as the guard of honur march near the monument of the unknown soldier early on June 15.

Protesters gesture and wave Greek flags in front of the Parliament during a rally against plans for new austerity measures, in central Athens on June 15. A 24-hour anti-austerity strike by Greece's largest labor unions crippled public services Wednesday, as the Socialist government was to begin a legislative battle to push through last-ditch cost-cutting reforms that will extend beyond its own term in office.

Riot police confront a protester during a general strike against government austerity plans, in Athens on June 15. Offices were closed and public transport on land and sea across Greece was seriously disrupted early today as a mass general strike got under way.

Riot police arrest a protester during a general strike against government austerity plans, in Athens on June 15.

A vegetable market worker stands beside a police cordon during a protest in front of the labour ministry in Athens, Greece on June 10. Greece's economy shrank far more than expected at the start of 2011, signaling a second wave of austerity measures prescribed by the EU and IMF will pile even more pain on a fractious society.

Demonstrators are arrested by riot policemen during violent clashes in Athens, Greece, May 11. Violent clashes broke out in Athens between riot police and protesters who marched to parliament during a nationwide strike against austerity measures.

A police officer in full riot gear sprays tear gas at a protester's head during clashes on May 11 in Athens, Greece.