Turkey on Sunday continued a major attack inside northwestern Syria on a Kurdish militia it has called a "terror army" that presents a danger to Turkish security.
One day earlier Turkey sent tanks and armored vehicles lumbering across the border with Syria to add to artillery and aerial invasions already underway against the YPG, which Ankara seeks to drive out of the Afrin region of Syria.
Turkey also announced Saturday that the aerial component of its "Operation Olive Branch" had struck 108 YPG targets, as NPR's Peter Kenyon tells our Newscast unit.
Turkey's incursion may heighten tensions with the United States, with which it has partnered but also quarreled.
The U.S. has repeatedly armed and trained the YPG, which it sees as a vital partner in its fight against ISIS. Ankara, however, sees the YPG as terrorists and too closely allied with another Kurdish militia, the PKK, which has operated inside Turkey for more than three decades. Both the United States and Turkey consider the PKK a terrorist group.
The Pentagon says it limits its assistance to the YPG to regions where ISIS is nearby. A U.S. general says he hopes Turkey's operation comes to a swift conclusion and that Ankara returns its focus to turning back ISIS, according to NPR's Kenyon.