Fighting rages amid Turkish push in Kurdish enclave in Syria

Intense fighting flared Monday as Turkish troops and their allies advanced on a Kurdish enclave in northwestern Syria, the third day of Ankara’s offensive to oust a U.S.-allied Kurdish militia from the area, according to the militia and a war monitoring group.

Skirmishes between Turkish troops and Kurdish fighters also broke out farther east in Syria, threatening to widen the scope of the new front in the Syrian war that pits Turkey against Washington’s main ally in the region.

The Turkish ground and air offensive on Afrin began Saturday, raising tensions in the already-complicated Syrian conflict and threatening to further strain ties between Turkey and the U.S., both NATO allies. Turkey says it aims to create a 30-kilometer deep “secure zone” in Afrin, the Kurdish-controlled enclave on its border.

The Turkish military announced late Monday its first fatality to the operation. It said a soldier was killed in a cross-border raid. A NATO statement said it has contacted Turkey over the offensive. NATO said Turkey has suffered from terrorism and has the right to self-defense but urged Ankara to do so in a “proportionate and measured way.”

NATO also said it has no presence in Syria but that as members of the coalition against Islamic State of Iraq and the Levant (ISIL) militant group, “our focus is on the defeat” of the extremists.

U.S. Defense Secretary Jim Mattis said Turkey has “legitimate security concerns” about Syria. Speaking to reporters traveling with him Sunday to Indonesia, he said diplomats are working on a solution to Turkey’s confrontation with the Syrian Kurdish fighters, known as the People’s Defense Units or YPG, who have been the key U.S. military ally in battling the ISIL in Syria. Turkey considers the YPG a terrorist group because of its ties to its own Kurdish insurgency. Mattis said Ankara gave the U.S. military advance notice of its Afrin offensive.

The U.S. has offered direct military and logistical support to a Kurdish-led group known as the Syrian Democratic Forces that spearheaded the fight against ISIL in Syria.

With the near total defeat of ISIL in both Syria and Iraq, the U.S. said it would create a 30,000-strong border force of existing Kurdish and Arab SDF members to ensure there would be no ISIL comeback.

That announcement has outraged Turkey, and Secretary of State Rex Tillerson has tried to walk back the U.S. position, saying it was portrayed incorrectly. The U.S. focus in recent years has been on eastern Syria. The area west of the Euphrates River, including Afrin, has been more of a problem for the U.S. because Turkey had said it would not accept a Kurdish military presence there.