Turkish fighter jets were seen taking off from the Incirlik base in southern Adana province towards Syria on Sunday afternoon.
According to information gathered by an Anadolu Agency correspondent in the area, some movement was seen at the 10th Tanker Base Command of Incirlik Base as part of the ongoing 'Operation Olive Branch'.
While some Turkish fighter jets took off from the base, others remained on alert. Meanwhile, military cargo planes kept arriving and leaving the base.
Turkish ground forces have started to move into Syria’s Afrin with Free Syrian Army, Turkish General Staff said earlier on Sunday.
The operation -- aimed at eliminating PYD/PKK and Daesh elements from Syria's Afrin -- was launched at 5 p.m. (GMT1400) on Saturday. It was being carried out under the framework of Turkey’s rights based on international law, UN Security Council’s decisions, self-defense rights under the UN charter and respect to Syria's territorial integrity, the military added.
Afrin has been a major hideout for the PYD/PKK 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 PYD/PKK group from Afrin, which sits atop a hill. The terror group has also used Amanos Mountains to penetrate from Syria into Turkey.
The PYD/PKK depends on Afrin to connect to the Mediterranean from northwestern Syria.
The terrorist organization has also threatened the gains made from Operations Euphrates Shield and Idlib de-escalation zone over Afrin.
A quarter of Syria land and 65 percent of Turkey-Syria border are currently under occupation of the terrorist organization.
Operation Euphrates Shield began in August 2016 and ended in late March 2017 to improve security, support coalition forces and eliminate the terror threat along the Turkish border.