Four men, including a policeman, were remanded in custody by a Turkish court on Wednesday over the death of an anti-government protester who was beaten during a June demonstration, local media reported.
The four were placed in detention by a court in the northwestern town of Eskisehir where student Ali Ismail Korkmaz, 19, died of a brain haemorrhage on 10 July after spending 38 days in a coma.
Prosecutor Orhan Cetingul said investigators were seeking to identify a further suspect, while three others have been released, the Dogan news agency reported.
Turkey was gripped in June by nationwide protests triggered after police cracked down on demonstrators seeking to save a park in Istanbul.
The violent police action angered many Turks and transformed defence of the park into a wider political protest movement against the Islamic-rooted government.
According to police, some 2.5 million people took to the streets in 80 towns over three weeks to protest at Prime Minister Recep Tayyip Erdogan, accused of becoming increasingly authoritarian and wanting to be "Islamise" Turkish society.
The subsequent clashes left five people dead, including one policeman, and more than 8,000 people were injured, according to the Turkish doctors' union.