Tahir Elci, 49, was shot in Diyarbakir city Saturday while making a press statement. Prime Minister Ahmet Davutoglu said authorities are investigating whether the attack directly targeted Elci or whether he died in the crossfire during shooting between the assailants and police.
Addressing mourners in Istanbul on Sunday, Pro-Kurdish party leader Selahattin Demirtas said Elci was the victim of a "political murder." He said the lawyer dedicated his life to peace, freedoms, and brotherhood, AP reported.
Elci, who was Kurdish, advocated peace between Kurdish rebels and Turkey's security forces. He was facing a criminal charge for defending the rebels, whom Turkey considers terrorists, during a news program.
Hundreds of people have been killed since a ceasefire between the PKK and Turkish security forces collapsed in July, reigniting a conflict in which some 40,000 people have died since it began in 1984.
Elci's killing was likely to fuel further unrest in Turkey's mostly Kurdish southeast.
A curfew had been called in the Sur district of Diyarbakir where the killing took place and security forces conducted operations to drive back the youth wing of the PKK.