Turkish police have used tear gas against protesters in Istanbul and Ankara. The demonstrators were marking the first anniversary of a protest that began a series of anti-government demonstrations last year.
Police used tear gas and water cannon against hundreds of demonstrators who had gathered on streets leading to Istanbul's Taksim Square on Saturday.
Officers blocked access to the square in anticipation of protests, following warnings by Turkish Prime Minister Recep Tayyip Erdogan that demonstrators should stay away from the square on the first anniversary of last year's protests.
The crackdown happened after protesters rallied on Istiklal Caddesi, one of Istanbul's largest shopping streets. Footage from the Dogan news agency showed police, some in plain clothing, detaining several people. Police briefly detained a CNN television crew during a live broadcast from the Istiklal, with a statement from authorities that a reporter was held for questioning about his identity documents.
Some 25,000 police were deployed in anticipation of the Istanbul demonstration, along with up to 50 water cannons.
There were also clashes in the capital, Ankara, where police used water cannon and tear gas against a group of protesters who were alleged to be throwing stones and fireworks.
Opposition groups had called for protests on Taksim Square, with Erdogan saying police had been given "clear instructions" to disperse the participants. Erdogan was quoted by the Anadolu agency alleging that anti-government activists wanted to "hurt the reputation" of Turkey.
"Some pseudo-artists, quasi-intellectuals, are calling for new riots to cause new destruction, new deaths, new pain, but the youth in Turkey will not permit this," he said on Friday evening.
Last year's protests, which peaked in late May and June, were sparked by a government plan to uproot trees at Gezi Park, which is adjacent to Taksim Square, to help make way for a shopping development. The square became a focal point for demonstrators who claimed Erdogan's government had become increasingly authoritarian.
Erdogan's style of government has since come in for renewed criticism, both domestically and internationally. The premier has been accused of censorship over bans imposed on social networking and media sites such as YouTube and Facebook.
His Justice and Development Party (AKP) has also been accused of playing a role in allowing the allegedly lax standards that led to the Soma mining disaster in western Turkey, in which more than 300 people died.
rc/msh (AP, AFP)