ATHENS, Greece (AP) — A 24-hour general strike in Greece shut down services across the country, forcing flight cancellations and school closures and leaving state hospitals functioning with emergency staff, while tens of thousands of protesters marched in central Athens.

Labor unions called the strike to protest continued austerity measures as Greece struggles to emerge from a financial crisis that wiped out a quarter of the country's economy and sent unemployment soaring to 26 percent. Youth unemployment reached nearly 60 percent during the crisis, which began in late 2009 after years of profligate government spending and lax fiscal management.

The strike forced airlines to cancel all international and domestic flights after air traffic controllers joined the labor action. Public transportation in Athens was also severely disrupted as bus, trolley and subway workers took part in the strike for several hours. Ferries were also tied up in ports.

Two demonstrations in central Athens were attended by about 30,000 people in total, police said, while 6,000 marched in the northern city of Thessaloniki.

To tackle the financial crisis, Greece has been dependent since 2010 on billions of euros in rescue loans from the eurozone and the International Monetary Fund. In return, Greece has had to push through painful austerity measures, including pension and salary cuts, and to overhaul its economy.

The country's progress in reforms has been closely monitored by international debt inspectors from the IMF, European Commission and European Central Bank. The conclusion of the latest round of talks has been delayed amid disagreements over several issues, including whether Greece faces a fiscal gap next year. Two days of talks in Paris between the government and the debt inspectors ended inconclusively Wednesday.

Finance Minister Gikas Hardouvelis, who attended the talks and briefed the prime minister and deputy prime minister Thursday, said the issues had not been concluded but that talks continued. He said there could be a small extension to the bailout "for technical reasons, for a very small period."

Frequent and often violent demonstrations greeted the start of the crisis and imposition of austerity measures, but there have been far fewer over the past two years. Some Athenians said they saw little hope that another strike would bring change.

"The strike is a minor thing. Something very significant must happen because we've reached the point of being on the verge of jumping out of windows," businessman Stamatis Fassoulis said.