The People's Protection Units (YPG) terrorists Wednesday launched retaliatory strikes on civilian-populated areas in Turkey after Ankara launched its Operation Peace Spring into northeastern Syria.

Two mortar shells were fired from Syria into Ceylanpınar district in southeastern Şanlıurfa province.

Six rockets launched by the YPG from Qamishli also hit Mardin province's Nusaybin district.

A house in the Akçakale district of Şanlıurfa was later hit in a mortar shell attack by the YPG.

No casualties were immediately reported following the attacks.

Turkey on Wednesday announced the launch of Operation Peace Spring east of the Euphrates River in northern Syria to secure its borders by eliminating terrorist elements to ensure the safe return of Syrian refugees and Syria's territorial integrity.

Turkey has said the terrorist group PKK and its Syrian extension the YPG constitute the biggest threat to Syria's future, jeopardizing the country's territorial integrity and unitary structure. Most of northeastern Syria is controlled by the U.S.-backed Syrian Democratic Forces (SDF), which is dominated by YPG terrorists.

The Defense Ministry said the Turkish forces are taking great care not to harm civilians and allied troops in the area.

The ministry also said Turkish operation in northeastern Syria is only targeting terrorists and their bases, weapons and tools.

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, children and infants.