Turkey said Sunday it suspects Islamic State fighters used chemical weapons against Turkish-backed rebels in northern Syria.
A Turkish military statement in the state-run Anadolu news agency says 22 rebels showed symptoms of exposure to "chemical gas" after a rocket attack east of al-Rai, near the Syria-Turkey border. The statement did not indicate when the attack took place.
The wounded were evacuated to the Turkish border town of Kilis where they are being tested for traces of chemical weapons, Turkish media reported.
There have been several episodes of chemical weapons being used against civilians and fighters in Syria since the civil war broke out in 2011, which would be a clear violation of international law.
A report in August by the Organization for the Prohibition of Chemical Weapons says there is enough evidence to pin responsibility for two chlorine gas attacks on the Syrian army and a mustard gas attack on Islamic State.
The Assad government denies being behind any chemical attacks, blaming them on "terrorists," its name for rebels.
Also Sunday, the Israeli military says it killed four gunmen with ties to Islamic State-affiliated militants in Syria.
Israel says its soldiers came under a machine gun and mortar attack on the Israeli side of the Golan Heights, along the Syrian border.
Military spokesman Peter Lerner said the soldiers returned fire while an Israeli military plane attacked the militants' vehicle, killing them.
Prime Minister Benjamin Netanyahu commended the Israeli soldiers Sunday.
"We are well prepared on our northern border and we will not allow any Daesh of hostile elements, under cover of the war in Syria, to establish themselves adjacent to our borders."
Daesh is the Arabic acronym for Islamic State.