Police have fired tear gas in running battles with stone-throwing youths in Athens, where a 48-hour general strike is being held against a parliamentary vote on tough austerity measures.
Thousands of protesters have gathered outside parliament in the capital where public transport has ground to a halt.
PM George Papandreou has said that only his 28bn-euro (£25bn) austerity plan would get Greece back on its feet.
If the package is not approved, Greece could run out of money within weeks.
Without a new plan in place, the EU and IMF say they will withhold 12bn euros of loans which Greece needs to repay debts due in mid-July.
'Declared war'
More than 5,000 police officers were deployed in the centre of Athens as the protesters marched towards parliament.
The rally started peacefully, but escalated into running skirmishes on the fringes of the main demonstration.
Hundreds of protesters with faces covered by scarves or gas-masks started throwing stones, debris and bottles at the police in one corner of the central Syntagma Square.
Police fired tear gas and stun grenades to keep them back.
http://www.bbc.co.uk/news/world-europe-13935400
Note: Update Record, 28 June 2011 Last updated at 17:05 GMT