A 48-hour public workers' strike has begun in Greece, as lawmakers discuss a new round of austerity measures required for another infusion of bailout funding from the European Union.

Police and anti-riot troops were out in force across the capital, Athens, Tuesday as more than 35,000 people marched through the city in two separate demonstrations organized by labor unions.

The strike grounded flights to and from the country for several hours while also halting taxi, train and ferry service. Schools and government offices are closed, and hospitals are operating on emergency staffing. The strike, which continues through Wednesday, is the third major walkout in two months.

Lawmakers began Tuesday to debate the austerity bill, which includes $17 billion in spending, benefit, and pension cuts. They will vote on the measure on Wednesday. If parliament rejects the package, Greece will run out of money by mid-November.

Greek Prime Minister Antonis Samaras has said that if parliament does not pass the measures, the country could be forced out of the eurozone.

Greece is in the fifth year of a recession. More than a quarter of its workforce is unemployed.