The Free Syrian Army (FSA) fighters launched a comprehensive operation against the terrorist PKK-linked People's Protection Units (YPG) dominated Syrian Democratic Forces (SDF) in Syria's Afrin early Sunday, a day after they entered the YPG-occupied territory as part of Turkey's "Operation Olive Branch" Saturday.
According to Anadolu Agency reporters on site, FSA fighters backed by the Turkish military started advancing toward the northern Syrian city in the early hours.
Military sources noted that the YPG militants are retreating to towns and villages following Turkey's Operation Olive Branch, in which Turkish tanks are backing Free Syrian Army (FSA) forces.
The Turkish General Staff confirmed earlier it launched "Operation Olive Branch" on Saturday at 5 p.m. (1400GMT).
"108 targets, which were used as shelters, hideouts and ammunition depots by terrorist organizations PKK/KCK/PYD-YPG and Daesh in seven areas, were destroyed by the air force," the military said in a statement late Saturday.
The operation was being carried out under the framework of Turkey's rights based on international law, U.N. Security Council's decisions and self-defense rights under the U.N. charter, the military added.
The statement said the operation will also take sensitivity into account and no civilian or innocent person would be harmed.
The YPG is the Syrian offshoot of the PKK terrorist group, which has been designated as a terrorist organization by Turkey, the U.S. and the EU.
Since the mid-1980s, the PKK has waged a wide-ranging terror campaign against the Turkish state in which an estimated 40,000 people have been killed.
Afrin has been a major hideout for the YPG since July 2012 when the Assad regime in Syria left the city to the terror group without putting up a fight.
The Turkish cities of Kilis and Hatay across the Syrian border are within the firing range of the YPG from Afrin, which sits atop a hill. The terror group has also used Amanos Mountains to penetrate into Turkey from Syria.
The YPG depends on Afrin to connect to the Mediterranean from northwestern Syria. The terrorist organization also threatens Idlib de-escalation zone over Afrin. A quarter of Syria land and 65 percent of Turkey-Syria border is under the occupation of the terrorist organization.
Turkey has been backing the Syrian moderate opposition FSA forces, and liberated Syria's al-Bab and cleared Daesh terrorists off the country's borders. Over 2,000 square kilometers of land in northern Syria had been liberated from Daesh terrorists, allowing some 100,000 people to return to their homes.