Hundreds of Turkish police have moved into Istanbul's Taksim Square, the site of ongoing demonstrations against the government, in what authorities claim is an effort to clean the area of banners.
Backed by armoured vehicles and wielding shields, the police on Tuesday moved past barricades set up by protesters, and blocked all exits as small groups of demonstrators fought back against the early morning intervention.
Protesters responded by throwing stones, petrol bombs and fireworks.
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The governor of Istanbul, Huseyin Avni Mutlu, said on Twitter that police were there only to remove banners and placards and the action was not targeting the removal of those people in the area. Banners from far-left groups were removed by the police.
A statement from Mutlu's office said the aim of the invervention was to remove the banners of various groups in the square, which were making it look as though it was under "occupation". This was "negatively affecting our country's image in the eyes of the world opinion and leading to reaction from within the society".
Taksim Square has been at the heart of anti-government demonstrations over the past two weeks. The protests were intially triggered by opposition to government plans for redeveloping the Gezi Park adjoining the square, before escalating into nationwide demonstrations against the government of Prime Minister Recep Tayyip Erdogan.
Al Jazeera's Emre Rende in Istanbul said police claimed they were not targeting those who were there to resist the redevlopment of the park.
He said police were repeating this statement on loudhailers: "People in Gezi Park, we will not hurt you or intervene. We want to help you", while telling protesters in Taksim Square to "stop throwing stones, stop throwing bottles and we will stop the teargas".
Erdogan has taken a defiant stand against anti-government demonstrations but on Monday said he was willing to meet with some of the leaders of the dissent.