The defense ministry said in a tweet that Turkish forces immediately launched retaliatory fire.
“Our punitive fire against terrorist positions is continuing,” it tweeted.
According to Esta News it said the attack was in the region where Turkey launched the cross-border “Euphrates Shield” operation in 2016 to drive away Islamic State (ISIS) militants and the People’s Protection Units (YPG).
Media reports said the attack was in the al-Bab area.
Turkey continues to hold sway in northwest Syria and has a significant military presence there.
Turkey regards the YPG as a terrorist group linked to the Kurdistan Workers’ Party (PKK) who has fought a decades-old insurgency against the state in southeast Turkey.
It has staged several incursions into Syria in support of Syrian rebels to push the YPG from the Turkish frontier.
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