One Turkish soldier was killed in an attack carried out by PKK terrorist group's Syrian affiliate People's Protection Units (YPG) near the area of Operation Olive branch in northern Syria, the Defense Ministry said Sunday.

The soldier was killed as a result of a mortar attack by the YPG while another soldier was also injured, the Defense Ministry's Press and Public Relations Department said in a statement, noting that the Turkish military immediately retaliated.

The Defense Ministry offered condolences to the family of the fallen soldier.

Turkish Armed Forces and their allies the Free Syrian Army (FSA) cleared the YPG elements from northern Syria's Afrin during Operation Olive Branch launched in January 2018.

The Turkish military and the FSA also cleared Syria's Al-Bab and Jarablus from Daesh terrorists in Operation Euphrates shield launched in August 2016.

In its more than 30-year terror campaign against Turkey, the PKK -- listed as a terrorist organization by Turkey, the U.S. and the EU -- has been responsible for the deaths of some 40,000 people, including women and children.