Turkish police fired tear gas and water cannon to disperse hundreds of protesters in an Istanbul square on Saturday as they gathered to enter a park that was the center of protests against Prime Minister Tayyip Erdogan last month.
The Taksim Solidarity Platform, combining an array of political groups, had called a march to enter the sealed off Gezi park, but the governor of Istanbul warned that any such gathering would be confronted by the police.
Riot police chased protesters into side streets in what appeared to be the biggest police intervention since the mid-June protests and riots that saw Taksim Square sealed off by makeshift barriers.
"We are here today to claim our park back. It was supposed to be open tonight. They (authorities) called us occupiers, but the park has been occupied by the state for weeks now," said 41-year-old web designer Asim Elci.
Protesters chanted "Together against fascism" and "Everywhere is resistance."
A police crackdown on a group protesting against the planned redevelopment of Gezi Park, a leafy corner of Taksim, triggered nationwide protests last month against Erdogan, accused by critics of increasingly authoritarian rule after a decade in power.
Turkish Halk TV showed protesters standing in front of riot police on Saturday, displaying a court decision cancelling plans for a replica Ottoman-era barracks on Taksim Square. The plan is one of a string of ambitious projects fostered by Erdogan, including a canal parallel to the Bosphorus waterway, a huge international airport and a giant mosque.
Authorities can appeal against the court ruling, which was considered a victory for the protesters and a blow for Erdogan, who stood fast against protests and riots he said were stoked by terrorists and looters.
Erdogan has carried out sweeping changes since he was elected in 2002 at the head of a party combining nationalists and reformers as well as Islamist elements. He had curbed the power of an army that had toppled four governments in 40 years and carried out some liberal social and economic reforms.
But critics, outside the party and some within, had grown increasingly uneasy at what they felt to be an authoritarian style. At the height of the protests he appeared to appeal increasingly to the Islamist and nationalist core of his party, further alienating secularists and other groups.
Four people were killed and about 7,500 wounded in the June crackdown, according to the Turkish Medical Association. It largely ended when police cleared a protest camp on the square on June 15.
Istanbul governor Huseyn Avni Mutlu said the authorities had not given permission for Saturday's rally.
"Our constitution allows staging demonstrations without giving notification, but the legislation says that applying to the authorities for permission is mandatory," Mutlu said, announcing on his twitter account that Gezi Park would be open to the public on Sunday.
"I cannot act against the law. So we won't allow these gatherings."
Mainstream Turkish media largely ignored the protests but Turks against the government used social networking sites such as Twitter and Facebook to share news of developments in Istanbul.