Fifty people were detained after rioters tossed bombs at police, who responded with tear gas, as Greek's parliament worked on a plan to cut government spending.
According to a report from Associated Press, the violent clash happened in Athens, and was the first demonstration of its type since a left-wing government took power earlier this year following a campaign against the austerity measures in the island nation.
Estimates were that more than 12,000 protesters also lit vehicles on fire and smashed storefronts as lawmakers were discussing more cutbacks, tax increases and pension reductions "that will condemn Greeks to years of more economic hardship," AP reported.
The changes are among the requirements for the nation to get more bailout money from the eurozone – funding that is needed to prevent Greece from crashing its economy entirely with defaults on international loans, which could force it to leave the euro entirely.
The economic hits were adopted by Prime Minister Alexis Tsipras in a marathon summit with other Eurozone leaders.
Finance Minister Euclid Tsakalotos told AP, "I don't know if we did the right thing. But I know we did something with the sense that we had no choice."
Strikes by public transportation workers and other civil servants followed.
Several public officials have resigned over the requirements imposed to obtain another $93 billion in loans.
The International Monetary Fund also was involved in two previous bailouts for Greece, AP reported.
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