Ali Ismail Korkmaz, 19, died of a brain hemorrhage July 10 after 38 days in a coma, sustained when he was allegedly beaten during a June demonstration. Four people, including a police officer, have been arrested, the Turkish newspaper Hurriyet Daily News reported.
Writing on his Twitter account, Justice and Democracy Party deputy and former Culture Minister Ertugrul Gunay said, "Nobody should talk about justice and victims in other countries before those who killed Ali Ismail Korkmaz get the penalty they deserve."
The video footage shows a man, allegedly Korkmaz, trapped and beaten by four men at a building entrance, the newspaper said.
A civilian suspect in the beating said a riot police officer told civilians to catch protesters so they could "beat them with sticks." The arrested police officer shouted at civilians to "catch protesters," the newspaper Radikal reported.
The July 10 demonstration as held to protest a government plan to create a replica of Ottoman military barracks in the place of Gezi Park in Istanbul.
Protesters' anger was fueled when police violently stopped a sit-in demonstration at Taksim Square May 31.