Turkey's largest city Istanbul has witnessed clashes between security forces and trade unionists trying to celebrate May Day. The clashes occurred after the government had refused trade union requests to hold celebrations in Taksim square, the traditional location for labor celebrations. Dorian Jones reports from Istanbul.

Protestors throw stones at riot police car during May Day clashes in Istanbul, 01 May 2008

"Long live May Day" thousands of workers chanted in the center of Istanbul. But the celebrations quickly descended into violence.

The police broke up the demonstrations firing tear gas into the crowds. While some of the protesters threw stones. Many of the streets resembled a battleground, littered with rocks and empty tear gas cartridges.

Police with batons charged many of the trade unionists, as shoppers looked on in disbelief. The headquarters of one the trade union confederations, had tear gas fired into it, with more clashes outside the building. Over 500 people were arrested and dozens are reported injured. Trade unionists condemned the police response.

"We are angry but we know we are right, we want just to protect our rights, but the government is against us and for this we are here and we want to go to Taksim," one person said.

Three of Turkey's largest trade union confederations had demanded the right to mark May day in Taksim square, which is the heart of the city. Taksim has major symbolic importance to the country's labor movement.

In 1977, more than 30 people were killed during May Day celebrations when unknown gunmen opened up fire on a crowd of a half million. After the military seized power, trade unions have been banned from celebrating May Day in Taksim square, but other gatherings are allowed. Despite intense lobbying by the unions the government refused to lift the ban.

Prime Minister Recep Tayyip Erdogan blamed illegal groups for the violence, adding that alternative places in Istanbul were available for May Day celebrations.