According to Ankara, Turkey's military retaliated after one of its soldiers had been killed and another one injured in a mortar attack in northwestern Syria.
The Turkish Defence Ministry stated that the attack was carried out by the Kurdish YPG militia, which has been fighting Daesh* in Syria mostly as part of the US-backed Syrian Democratic Forces, in the Afrin region.
"After the incident, targets identified as belonging to terrorists were subject to fire," the Turkish ministry said in a statement.
Last year, Turkey launched a military operation against the Kurdish-controlled enclave of Afrin in the north of Aleppo province in Syria, fighting the Kurdish People's Protection Units (YPG), which constitute a part of the US-backed Syrian Democratic Forces (SDF). Ankara views YPG as an affiliate of the Kurdistan Workers' Party (PKK), considered a terrorist organisation by Turkey.
*Daesh (also known as Islamic State, ISIS, ISIL, IS) is a terrorist group banned in numerous countries, including Russia