Footage circulated on social media showing a vehicle with a registration plate of the Kurdistan Region was bombed in Shingal town.
AFP cited a security source as saying that Hassan Saeed died along with two comrades as their car was hit on the road to Shingal, the heartland of the Yazidi religious community.
Saeed headed the Shingal Resistance Units, set up in 2014 to protect the Yazidis from the Islamic State (ISIS) group before being integrated into Hashid al-Shaabi.
Meanwhile, the YBS said in a statement that the strike had targeted one of its members.
The incident came after Turkish defense ministry said four soldiers were killed and two others were wounded in attacks by PKK fighters in the Kurdistan Region.
Turkish forces routinely conduct operations against PKK bases in rugged mountains in the Kurdistan Region.
On Friday, a Turkish airstrike killed a 50-year-old man in Disheshe village in Kani Mase sub-district, northeast of Duhok.
Turkish troops have maintained a network of bases in Iraq since the mid-1990s under security agreements struck with Saddam Hussein’s regime.
The PKK has waged a rebellion in the mainly Kurdish southeast of Turkey since 1984 for kurdish rights in the countrt.
The PKK’s pan-Kurdish agenda has often put it at odds with the Kurdistan Region, which has sought to maintain good relations with Ankara.
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