Greek police have fired tear gas at protesters in Athens after some demonstrators hurled gasoline bombs at them, as tens of thousands of people demonstrate against the latest round of austerity measures.

Workers walked off the job Wednesday, closing schools, canceling flights and shutting down shops and services across the country.

Greece is required to make $15 billion in spending cuts over the next two years, in order to obtain its next round of international aid.

The majority of those cuts are expected from slashing wages, pensions and welfare benefits.