ISTANBUL - Riot police fired tear gas, water cannons and rubber bullets in daylong clashes that lasted into early today, battling protesters who have been occupying Istanbul's central Taksim Square and its adjacent Gezi Park in the country's most severe anti-government protests in decades.
The crisis has left Prime Minister Recep Tayyip Erdogan looking vulnerable for the first time in his decade in power and has threatened to tarnish the international image of Turkey, a Muslim-majority country with a strongly secular tradition, a burgeoning economy and close ties with the United States.
Throughout the protests, Erdogan has maintained a defiant tone, insisting he would not be bowed by what he described as a vocal minority. On Tuesday, as police clashed with protesters in Taksim, he insisted again that the unrest was part of a conspiracy against his government.
The demonstrators, he said, "are being used by some financial institutions, the interest rate lobby and media groups to (harm) Turkey's economy and (scare away) investments."
A peaceful demonstration against the park's redevelopment that began more than two weeks ago has grown into the biggest test of Erdogan's authority, sparked by outrage over a violent police crackdown on May 31 against a peaceful sit-in at the park.
The unrest has spread to 78 cities across the country, with protesters championing their objections to what they say is the prime minister's increasingly authoritarian style and his perceived attempts to impose a religious and conservative lifestyle on a country with secular laws - charges he rejects.
Four people have been killed, including a policeman, and about 5,000 have been treated for injuries or the effects of tear gas, according to the Turkish Human Rights Foundation.
Thousands of police moved in early Tuesday, pushing past improvised barricades set up by the protesters who have swarmed through the massive square and park in tens of thousands for 12 days.
Police fired repeated rounds of tear gas that rose from the square in stinging plumes of acrid smoke in running battles with groups of protesters hurling fireworks, bottles, rocks and firebombs in a cat-and-mouse game that lasted through the day and into the night.
More than 30,000 converged on the square again as dusk fell and were repelled by water cannons, rubber bullets and tear gas after Istanbul's governor, Huseyin Avni Mutlu, said the police came under attack from "marginal groups."
By early today, cleanup crews had moved into Taksim Square, clearing the debris and dismantling the makeshift shelters the protesters had set up.
Protesters set up barricades of metal railings and smashed vehicles at the edge of the square leading into Gezi Park, where hundreds returned despite repeated rounds of tear gas being fired into their midst. Fearing injury, many protesters scrawled their blood type on their forearms with marker pens.