Riots engulfed central Athens and at least 10 buildings went up in flames in mass protests as lawmakers prepared for a historic parliamentary vote on harsh austerity measures demanded to keep the country solvent and within the eurozone.
Protesters set bonfires in front of parliament and dozens of riot police formed lines to try to deter them from trying to make a run on the legislative building on Sunday evening.
Many in the crowd wore gas masks and had their faces covered, prepared for the clouds of tear gas that drifted across the square.
Several protesters and police were injured, while an unspecified number of suspected rioters were detained, authorities said.
Clashes erupted after more than 100,000 protesters marched to parliament to rally against drastic austerity cuts that will ax one in five civil service jobs and slash the minimum wage by more than a fifth.