Athens, February 4 (RHC)-- Main labor unions in Greece observed a 24-hour strike against the government's pension reform plans on Thursday, bringing Greece to a standstill.  The strike paralyzed most public transportation, grounded domestic flights and ducked ferries in ports.

About 50,000 Greeks marched on parliament Thursday, carrying banners and flags and chanting anti-bailout and anti-government slogans. Black-clad youths hurled stones and petrol bombs at police, who responded with rounds of tear gas and stun grenades, Reuters reported.

The government of Prime Minister Alexis Tsipras, first elected just over a year ago on a platform of anti-austerity policies, is under pressure from all sides. He is stuck between either bowing to creditors' demands for more stringent measures or siding with thousands of Greeks opposed to such plans. 

Denouncing the reform plans, the General Confederation of Greek Workers (GSEE) demanded in a statement that the government "revoke this monstrosity." The walkout is the second nationwide strike since Prime Minister Tsipras came to power in January 2015.