ATHENS - Thousands of protesters demonstrated in Athens on Thursday against austerity measures demanded by the new unity government to persuade its creditors to release bankruptcy-saving loans.
"We will throw all of them out," promised a banner held aloft by students, while another carried by anarchists read: "In the face of tyranny, one must choose between chains and arms."
At least 4,000 people had joined a first protest by students and unionists, police said, ahead of a second march by communists in the early evening.
Twenty youths were detained by police ahead of the demonstration.
Greece is slogging through a third year of recession exacerbated by wage cuts and tax hikes imposed by the previous socialist government of George Papandreou.
These are set to continue under the new coalition administration set up last week under former European Central Bank deputy chief Lucas Papademos, as he seeks to implement reforms demanded by EU and International Monetary Fund creditors.
"We have no money, no jobs, no future in this country," said Sotiris Kirbas, a 52-year-old unemployed man who joined the protest. "The crisis is not only about numbers, it's about people."
Police deployed 7,000 officers across Athens for the demonstrations, seen as a test of the scale of public defiance against the new government.
Hundreds of riot officers wearing body armour and equipped with tear gas, gas masks, batons and shields formed protective lines outside state buildings and embassies that are regularly targeted during protests.
The march on November 17 each year commemorates a student uprising at the Athens Polytechnic in 1973 in which at least 44 people died but which helped topple a US-backed army dictatorship and brought back the republic.
The bloodstained Greek flag that flew over the university that night is carried at the head of the demonstration, which passes in front of parliament and EU offices, before culminating at the US embassy.
The participation of far-right politicians in the cabinet for the first time since democracy was restored in 1974 has added to the outrage of the protesters during this year's demonstrations.
"Down with the government of socialists, conservatives and fascists," a protester banner said.
Tempers flared on Wednesday after leftist students prevented youth members of the socialist party - which also shares power in the government - from laying a wreath at the Polytechnic.
Last year, police fired tear gas and arrested more than 20 people after clashes broke out on the sidelines of the 20,000-strong demonstration.
The socialist, conservative and far-right nationalist parties formed a coalition last week to save Greece from looming bankruptcy, and they must now approve a crucial eurozone debt bailout before holding early elections.
"We have an economic and political junta," said Marita, a 23-year-old civil engineering student enrolled at the Polytechnic.
"We have a government that did not emerge from elections, nobody asked us. What is this, if not a junta?" she told AFP.
The new government was officially confirmed in parliament late on Wednesday, with 255 out of 300 lawmakers showing their support in a vote of confidence.
But Greece's third largest party, the Communists, and the smaller leftist Syriza party have pledged to fight to bring down the government to prevent further belt-tightening after two years of austerity.
"The Greek people won their independence through struggle. Anybody who tries to deprive them of it will pay dearly," said Syriza leader Alexis Tsipras.
Papademos must secure the latest installment of a 2010 bailout to avert bankruptcy by mid-December, when the state coffers run dry, and enforce reforms agreed as part of a second rescue deal agreed last month.