The conflict happened in and around Taksim Square, where the government had forbidden gathering in large numbers.
Prime Minister Recep Tayyip Erdoğan warned protesters he would do "whatever is necessary" to disperse the crowds, according to the AP.
Thousands of police were on scene in Istanbul Saturday to control the crowds, according to the BBC. The police attempted to block access to the square itself.
Protests also took place Saturday in Ankara, the capital of Turkey.
The AP reports that 14 people were injured Saturday in Istanbul, with dozens more detained by police.
Saturday's conflicts came on the one year anniversary of anti-government demonstrations in Ankara that left eight dead and thousands wounded.
Last year's protests were sparked by outrage over a redevelopment plan of Gezi Park, near Taksim Square. The protests later expanded to other cities and grew to include an array of other issues.
Hundreds of people reportedly participated in Saturday's protests, with many fighting back against police.
Jim Dalrymple is a reporter for BuzzFeed News and is based in Los Angeles.
Contact Jim Dalrymple II at firstname.lastname@example.org.
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