Turkish warplanes conducted a barrage of air strikes on Kurdish positions in northeast Syria early Tuesday, leaving several fighters dead, Kurdish forces and a monitor said.
The decision to hit positions held by the PKK across Turkey's borders was made after a slew of attacks against military outposts near borders with Iraq and Syria, the military said.
"Three YPG members working in the media centre were killed", Observatory head Rami Abdel Rahman told AFP.
Yawar and other officials said the overnight strike apparently targeted a Yazidi militia allied with Turkey's Kurdistan Workers' Party (PKK) which Ankara, a key ally of the Iraqi Kurdish government, considers a terrorist organisation.
"Nine others were also wounded by the air strike on the Sinjar mountain", he said, in reference to a northwestern region of Iraq which is the main hub of the Yazidi minority. The claim could not be independently confirmed.
Founded in 1978, the PKK has waged a decades long bloody campaign against Turkey.
Turkey launched the operation in August to fight the Islamic State group and to keep the YPG in check.
PKK - listed as a terrorist organization by Turkey, the USA, and European Union - resumed its armed campaign against Turkey in July 2015 and since then has been responsible for the deaths of approximately 1,200 security personnel and civilians, including women and children.
The bombings are a bloody example of the diplomatic challenges facing Donald Trump as the United States tries to rally its allies for a final assault against Raqqa, Isil's de facto capital in northern Syria.
"By this attack, Turkey is trying to undermine Raqqa operation, give (IS) time to reorganize and put in danger lives of thousands of" displaced, the YPG said on its Twitter account.