The United States and Turkey are finalizing plans for a military campaign to push the Islamic State group out of a strip of Syrian territory along the Turkish border, a move that would further embroil Turkey in Syria's civil war and set up a potential conflict with U.S.-backed Kurdish forces.
A U.S. official said the creation of an "Islamic State-free zone" would ensure greater security and stability in the Turkish-Syrian border region. However, the official said any joint military efforts with Turkey would not include the imposition of a no-fly zone. The official insisted on anonymity because this person was not authorized to publicly discuss the talks with Turkey.
The U.S. has long rejected Turkish and other requests for a no-fly zone to halt Syrian government air raids, fearing it would draw U.S. forces further into the civil war.
The discussions come amid a major tactical shift in Turkey's approach to the Islamic State. After months of reluctance, Turkish warplanes started striking militant targets in Syria last week, following a long-awaited agreement allowing the U.S. to launch its own strikes from Turkey's strategically located Incirlik Air Base.
But in a series of cross border strikes since Friday, Turkey has not only targeted the IS group but also Kurdish fighters affiliated with forces battling the extremists in Syria and Iraq. The Syrian Kurds are among the most effective ground forces battling the IS group and have been aided by U.S.-led airstrikes, but Turkey fears they could revive an insurgency against Ankara in pursuit of an independent state.
It was not immediately clear how an IS-free zone would be established along the Turkish-Syrian border, most of which is controlled by the Kurds. Syria's main Kurdish fighting force is affiliated with the Kurdistan Workers' Party, or PKK, which waged a decades-long insurgency in Turkey and maintains bases in remote parts of northern Iraq.
On Monday Syria's main Kurdish militia and an activist group said Turkish troops had shelled a Syrian village near the border, targeting Kurdish fighters.
The Kurdish People's Protection Units, or YPG, said the Sunday night shelling on the border village of Til Findire targeted one of their vehicles. It said Til Findire is east of the border town of Kobani, where the Kurds handed a major defeat to the Islamic State group earlier this year.
But Turkish officials dismissed the claims, insisting their forces were only targeting the IS group in Syria, and the PKK in neighboring Iraq.
A government official said Turkey returned fire after Turkish soldiers at the border were fired upon, in line with Turkey's rules of engagement.
"The Syrian Kurds are not a target of the operations. Our operations only target IS in Syria and PKK in Iraq," he said.
The Turkish official said authorities were "investigating claims that the Turkish military engaged positions held by forces other than ISIS." The official spoke on condition of anonymity because of rules that bar officials from speaking to journalists without authorization.
The YPG did not say in its Monday statement whether there were casualties in the shelling.
The YPG said Turkey first shelled Til Findire on Friday, wounding four fighters of the rebel Free Syrian Army and several local villagers. It urged Turkey to "halt this aggression and to follow international guidelines."
The Britain-based Syrian Observatory for Human Rights said four fighters were wounded in the village of Zor Maghar, which is also close to the Turkish border. Conflicting reports are common in the aftermath of violent incidents.
Earlier this month, Syria's main Kurdish party, the Democratic Union Party, or PYD, warned Turkey that any military intervention would threaten international peace and said its armed wing, the YPG, would respond to any "aggression."
Turkish police meanwhile raided homes in a neighborhood in the capital on Monday, detaining at least 15 people suspected of links to the Islamic State group, the Turkish state-run news agency said. The Anadolu Agency said those detained in Ankara's Haci Bayram neighborhood include a number of foreign nationals, without naming their home countries.
Turkey has arrested hundreds of people with suspected links to violent extremists.
On Sunday, it called for a meeting of its NATO allies to discuss threats to its security, as well as its airstrikes.
In comments published Monday, Turkish Prime Minister Ahmet Davutoglu said Turkey and the United States had no plans to send ground troops into Syria but said they had agreed to provide air cover to moderate Syrian fighters.
"If we are not going to send land units to the ground — and we will not — then those forces acting as ground forces cooperating with us should be protected," Davutoglu told a group of senior journalists over the weekend. His comments were published in Hurriyet newspaper.
Davutoglu also said Turkey wanted to clear its border of IS extremists.
"We don't want to see Daesh at our border," Hurriyet quoted Davutoglu as saying, using the Arabic acronym of the group. "We want to see the moderate opposition take its place."
The Turkish leader also said Turkey's action against the IS has "changed the regional game."
Despite the U.S. and Turkey's shared interests in fighting the Islamic State, the Turks have also prioritized defeating Syrian President Bashar Assad. While the U.S. says Assad has lost legitimacy, it has not taken direct military action to try to remove him from office.