Turkish police on Wednesday fired water cannons and tear gas at hundreds of protesters who had gathered to mark the first anniversary of the death of a teenager fatally wounded during anti-government demonstrations.
Mainly leftist protesters chanting "Berkin Elvan is immortal" clashed with police in Istanbul and Ankara.
Berkin Elvan, 15, was hit in the head by a tear gas canister after leaving his house to buy bread during violent anti-government protests that wracked Istanbul in June 2013.
He fell into coma and died nine months later on March 11, 2014. His death sparked further protests among those angry over a lack of prosecutions.
President Recep Tayyip Erdogan, prime minister at the time of the 2013 protests, said Elvan was linked to "terrorist" groups.
The 2013 protests posed one the biggest challenges to Erdogan, in office since 2003, but his opponents failed to make inroads at the ballot box. The next election is slated for June, when Erdogan hopes his AK Party will gain enough seats in parliament to create a strong executive presidency.
In Elvan's neighborhood of Okmeydani, almost 1,000 protesters marched towards the cemetery where Elvan was buried, then attempted to rush armored police vehicles that fired water cannons. Police chased protesters into side streets using tear gas and rubber bullets, witnesses said.
At Gezi Park in central Istanbul - the center of the 2013 protests - police detained eight high school students who splattered the area in red paint meant to resemble blood and unfurled a banner saying "Berkin is here."
In the capital, Ankara, police detained 11 people who had blocked traffic in the working-class district of Tuzlucayir, Hurriyet newspaper reported on its website.
Tuzlucayir is largely inhabited by members of the Alevi faith, as was Elvan.