Turkey has issued arrest warrants for 48 PKK and PYD members, including several senior figures, over a bombing in Ankara earlier this year.
The co-chair of the PYD, Salih Muslim, is among those named in connection with the attack that killed 29 people and injured dozens near the military head quarters and parliament building in Ankara.
The PYD is the political arm of Syria's YPG militia.
Turkey says the YPG is the Syrian branch of PKK, which Ankara, the EU and the US have designated as a terrorist organization.
More than 40,000 people have been killed since the PKK began its armed campaign against the Turkish state in 1984.
Top PKK figures Cemil Bayik, Murat Karayilan, Fehman Huseyin, Zubeyir Aydar and Remzi Kartal are also among the 48 people sought under the warrant, Anadolu Agency reported.