Turkish police fired tear gas and water cannon at hundreds of stone-throwing May Day protesters, after they defied a ban and tried to march on Istanbul's Taksim Square.

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An elderly man attempts to get up off the ground after Turkish police used a water cannon to disperse protesters during a May Day rally near Taksim Square in IstanbulBulent Kilic/AFP

Thousands of police manned barricades and closed streets to stop demonstrations at Taksim, a traditional rallying ground for leftists that saw weeks of unrest in 2013.

Riot police unleashed water cannon and chased protesters down side streets in the nearby Besiktas neighbourhood, where they fired off canisters of tear gas. Demonstrators lobbed stones and bottles at police and set off fireworks.

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Protesters prepare Molotov cocktails during a May Day rally near Taksim Square in IstanbulYasin Akgul/AFP
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Masked protesters hold unlit Molotov cocktails during a May Day rally near Taksim SquareOzan Kose/AFP
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A protester holds a Molotov cocktail near another using fireworks against riot police during a May Day rally near Taksim Square in IstanbulOzan Kose/AFP
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A masked protester launches fireworks towards Turkish riot police during a May Day rally at Okmeydani in IstanbulGurcan Ozturk/AFP
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A masked protestor throws a Molotov cocktail towards Turkish riot police during a May Day rally at Okmeydani in IstanbulGurcan Ozturk/AFP
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A man takes cover behind as Turkish police use a water cannon to disperse protesters during a May Day rally near Taksim Square in IstanbulBulent Kilic/AFP
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A man lies on the ground near a destroyed sign made with red and white carnations and a banner reading "Struggle" after Turkish police used a water cannon to disperse protestersBulent Kilic/AFP
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A protester takes cover behind a banner during clashes with police in IstanbulMurad Sezer/Reuters

Istanbul police said around 140 people had been detained, although activists said the number was nearly double that.

The Istiklal shopping avenue leading to Taksim was deserted, with shops shuttered and metal barricades blocking off side streets. Police helicopters circled overhead. A usually bustling square lined with cafes and hotels, Taksim was filled with police buses, ambulances and satellite broadcast trucks.

Much of Istanbul's public transport had been shut down due to security concerns, and police helicopters circled over the city.

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Masked protesters with Molotov cocktails in their hands play football during a May Day rally at Okmeydani in IstanbulYasin Akgul/AFP
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A protester uses a catapult during clashes with police in the Okmeydani neighbourhood of IstanbulHuseyin Aldemir/Reuters
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A masked protester prepares to throw a smoke bomb at riot policeOzan Kose/AFP
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A protester walks through the rubble during clashes with police in the Okmeydani neighbourhood of IstanbulHuseyin Aldemir/Reuters
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Plainclothes policemen detain a protester during clashes in the Besiktas neighbourhood of IstanbulMurad Sezer/Reuters
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Plainclothes policemen detain protesters during clashes in the Besiktas neighbourhood of IstanbulBurak Kara/Getty Images
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Turkish police detain a protester wearing a gas mask during a May Day rally near Taksim SquareBulent Kilic/AFP
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A protester is detained by police during clashes in the Okmeydani neighbourhood of IstanbulHuseyin Aldemir/Reuters
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Two protesters rest during clashes with police in the Okmeydani neighbourhood of IstanbulHuseyin Aldemir/Reuters

Critics say President Tayyip Erdogan and the government have become more authoritarian in the buildup to June elections. Erdogan has previously dismissed protesters as "riff-raff" and terrorists, outraged by the unrest in 2013 that brought unwanted international attention and posed the biggest challenge to his AK Party since it came to power in 2002.

He is aiming for a massive victory in June parliamentary polls, which would allow a change to the constitution and give him broad presidential powers.

The 2013 Taksim protests began as a peaceful demonstration against plans to redevelop Gezi Park, a leafy corner of the square. After a police crackdown the demonstration spiraled into weeks of nationwide protests against Erdogan's rule.