Tens of thousands of Albanian opposition supporters marched peacefully through the capital Friday to demand the government resign over corruption allegations, almost a month after four people died when a similar demonstration turned violent.

Hundreds of police guarded the main government building in Tirana, where dozens of protesters and police were injured in the Jan 21 riot. But the protest ended peacefully.

The opposition Socialists are demanding that conservative Prime Minister Sali Berisha hold early elections over allegations of corruption and vote rigging in the 2009 general election.

Shouting "Sali go," and "Prime Minister you are a murderer," as loudspeakers played somber music, protesters filled Tirana's main boulevard. Crowd estimates differed wildly, with opposition officials claiming some 200,000 people took part in the demonstration - compared to a police estimate of 7,000.