Turkey and the US have discussed a plan to drive the Islamic State of Iraq and the Levant (ISIL) group from a strip of Syrian territory along the Turkish border, officials say.
The plan opens the possibility of a safe haven for tens of thousands of displaced Syrians but also sets up a potential conflict with Syrian Kurds' YPG forces in the area.
The discussions with the US come ahead of a NATO meeting on Tuesday in Brussels, called at Turkey's request, to discuss Ankara's campaign against ISIL in Syria and Kurdish fighters in Iraq.
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John Kirby, a senior US Pentagon official, told a news conference that the discussions with Turkey about a safe zone focused on a 110km stretch of land still under ISIL control.
The US has been conducting air strikes there, which could accelerate now that it can launch strikes from Turkish soil.
Ankara and Washington aimed "to establish an ISIL-free zone and ensure greater security and stability along Turkey's border with Syria," he said.
Any joint military efforts would not include the imposition of a "no-fly zone" - a long-standing Turkish demand - but would enable Turkey to support US "partners on the ground" already fighting ISIL in Syria, an official earlier told AFP.
However, many question whether Turkey is more interested in limiting Kurdish capabilities in Syria and Iraq than tackling ISIL.
The YPG has proved to be the most effective force in Syria against ISIL and the Syrian government, but its successes have been eyed suspiciously by Turkey because of its links to its own country's Kurdistan Workers' Party (PKK), which it considers a "terrorist" organisation.
'Investigation' over shelling Syrian Kurds
Turkey on Monday denied its military was targeting the YPG in Syria after Kurdish forces and a monitoring group claimed its tanks shelled Kurdish-held villages in northern Syria.
Turkey has said it is investigating reports of the shelling on Sunday night.
If confirmed, the incident would be the most serious incident yet of Turkey targeting Kurdish-controlled areas in the Syrian conflict.
|Thousands of Kurds in Turkey and elsewhere have protested against Turkey's shelling of Kurdish targets [EPA]
Kurdish officials told Al Jazeera on Monday that overnight shelling targeted a checkpoint in a village outside Kobane manned by the Burkan al-Furat (Euphrates Volcano) battalion, a coalition of fighters from the Free Syrian Army and the Kurdish People's Protection Units (YPG).
The Syrian Observatory for Human Rights said four fighters were injured in the shelling.
"A number of shells fired by Turkish tanks fell on the village of Zur Maghar, which is controlled by the Kurdish People's Protection Units [YPG]," the UK-based monitoring group said.
Zur Maghar lies in Aleppo province, along the border with Turkey.
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Turkey began bombing what it described as ISIL targets in Syria on Friday, and the following day began pounding Kurdish targets in northern Iraq.
The campaigns followed a suicide attack claimed by ISIL that killed 32 young Kurdish volunteers in the border town of Suruc. They were about to deliver aid across the border to Kurds in Syria's Kobane.
The PKK responded to the attack by killing two Turkish police officers, claiming they collaborated with ISIL in the bombing.
On Monday night, gunmen in the Mus province, a predominantly Kurdish part of eastern Turkey, shot a paramilitary police commander. The officer later died in hospital of his injuries.
No one immediately claimed responsibility for the killing.
|Kurdish demonstrators protest near the Turkish embassy in Paris as claims emerge that Turkey is targeting Kurds in Syria [AP]
Source: Al Jazeera and agencies