Istanbul (CNN) -- Riot police fired tear gas and water cannons Wednesday at hundreds of protesters trying to hold May Day demonstrations in Istanbul's iconic Taksim Square in defiance of a ban. The clashes came as police locked down all roads leading to Istanbul's main commercial district, after barring the annual Labor Day rally in Taksim Square for the first time in three years. Despite the shutdown, riots raged throughout densely populated parts of central Istanbul as demonstrators tried to reach the traditional May Day rally site. Activists and government officials traded accusations about who was responsible for the tensions.
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Riot police fire tear gas and water cannons at protesters trying to reach Taksim Square
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Authorities say they barred access to the square because of construction work in the area
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Trade unions and youth groups say Taksim Square is the historic site of May 1 activities
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Istanbul authorities and human rights groups disagree on the number of people injured
Youth groups have been canvassing @placeholder with posters that read, "Bring your anger, and come to Taksim."