By Alkman Granitsas and Nick Skrekas Of DOW JONES NEWSWIRES ATHENS (Dow Jones)--Thousands of demonstrators took to the streets of Athens Tuesday with public services across Greece disrupted as the country''s two major unions staged a 24-hour strike over proposed pension and labor reforms. The protest and strike, called by private sector umbrella union GSEE and its public sector counterpart ADEDY, is the latest general strike this year and comes just as Greece''s parliament is set to consider the proposed reforms. The unions vowed further strike action next week as the reforms are voted on. "It was a very large gathering and march, and strike participation is higher than at other times," said GSEE President Yannis Panagopoulos. "Naturally we will strike next Wednesday or Thursday again when thebills will be voted on in parliament." According to police estimates, 10,000 protesters participated in three separate demonstrations, though union organizers said more than 50,000 had taken part. However, the mostly peaceful protests were marred when left-wing youth began hurling objects at police, smashing paving stones and setting trash bins on fire. At least one policeman was injured in the central square of Omonia when he was hit in the head by a rock thrown by a protester. Riot police responded with tear gas and stun grenades. By the standards of recent Greek protests--including a May 5 strike that turned violent and left three people dead--Tuesday''s clashes were minor and participation was low. Many analysts said the recent violence has scared away many would-be demonstrators. "The labor protests have weakened," said George Kyrtsos, a political commentator and editor of the City Press newspaper. "It has become kind of a ritual now, and these labor protests in Greece don''t have much meaning any more." The reforms are part of a three-year austerity program being undertaken by the Greek government in exchange for an EUR110 billion bailout package agreed last month with the European Union, the European Central Bank and the International Monetary Fund. But the move to reform Greece''s pension and labor laws in particular is seen as a major test for the ruling Socialist party which is facing discontent in its own ranks as well as the resistance of the unions. Later Tuesday, the Greek parliament will begin consideration on the reforms which includes measures to raise retirement ages, cut pension benefits, lower minimum wages and make it easier for employers to lay off workers. As part of the strike, local and central government offices were closed, while hospitals, ambulance services and state-owned companies were operating with skeleton staff. Local transport inthe capital, Athens, was disrupted by a series of work stoppages in public transport, while rail services around the country were suspended. Dozens of domestic flights were canceled as air traffic controllers at smaller, regional airports walked off the job, but international flights into and out of Athens were not affected. Greek journalists were also taking part in the strike, with regular news shows replaced by alternative programs. In the Athens port of Piraeus, Communist-affiliated dock workers defied a court injunction and pushed their way into the embarkation area, forcing the cancellation of more than a dozen ferry services Tuesday. Even so, the government said it would push ahead with reforms, even in the face of discontent. "At the end of the day, it is very clear that this bill is a cornerstone of the reforms," said Finance Minister George Papaconstantinou. "I''m not worried about disruptive protests, even though there will be protests, they are less than in other countries where lesser measures have been taken." -By Alkman Granitsas, Dow Jones Newswire