The Turkish military says three of its soldiers have been killed and 10 more wounded in Syria by an air strike allegedly launched by Syrian regime forces.
A statement from the Turkish armed forces on its website said that the attack occurred at 3:30am local time [00:30 GMT] on Thursday.
"In the air strike assessed to have been by Syrian regime forces, three of our heroic soldiers were killed and 10 soldiers wounded, one seriously," it said in the statement.
It did not say where the attack occurred, but Turkish news media said the location was near the northern Syrian city of Al Bab.
"This would be the first time any Turkish combat troops have been killed inside Syrian territory, by Syrian forces," said Al Jazeera's Osama Bin Javaid, reporting from Gaziantep on the Turkish side of the Turkish-Syrian border.
"But we have to emphasize this claim is so far coming only from the Turkish military," he said.
"They are saying that they believe it was an attack by the Syrian air force."
Referring to the ISIL group, he said: "Earlier in the day, we heard claims from several Syrian pro-regime websites saying that this attack was carried out by ISIL."
In September, three Turkish soldiers were killed and one was wounded during clashes with ISIL fighters in northern Syria.
In August, one Turkish soldier was killed and three others were wounded in a rocket attack on a Turkish tank south of Jarablus. Turkish military blamed that attack on Kurdish YPG fighters.
The latest casualties are expected to escalate tensions between Turkey and Syria.
On August 24, Turkey sent ground troops into northern Syria to support Syrian opposition fighters in its stated fight against ISIL, also known as ISIS, and to curb Syrian Kurdish territorial gains.
At the moment, the Turkish troops are not engaged in combat with Syrian regime forces.
"Turkey has a significant presence in northern Syria," said Al Jazeera's Javaid. "It has already cleared the town of Jarablus from ISIL and it is now moving towards the second ISIL-held city in the region, Al Bab.
After it takes Al Bab, Turkish military says its aspirations are that it will clear the whole area and it will retake the town of Manbij from SDF, the largely Kurdish."
Turkey views Syrian Kurdish troops as an extension of the Kurdistan Workers' Party (PKK), an armed group that has been battling government forces in southeastern Turkey for decades.
PHOTO CAPTION
A Turkish soldier on an armored personnel carrier waves as they drive from the border back to their base in Karkamis on the Turkish-Syrian border in the southeastern Gaziantep province, Turkey, August 27, 2016. REUTERS
Al-Jazeera