NUSAYBIN, Turkey, Jan 20 (Reuters) - Turkey said on Tuesday it was investigating the burning of its flag during protests along its border with Syria by pro-Kurdish groups, coinciding with clashes there between the Damascus government army and Kurdish-led forces.
Syrian government forces pushed deeper into northeast Syria's Kurdish-held areas on Tuesday after taking swathes of territory long held by the Kurdish-led Syrian Democratic Forces (SDF) this week, advancing President Ahmed al-Sharaa's effort to bring all the entire country back under centralised authority.
Ankara, the main foreign supporter of Sharaa's government, deems the SDF a terrorist organisation linked with outlawed Kurdish PKK militants in Turkey, and has repeatedly said the SDF must integrate into Syria's state apparatus under a 2025 accord.
Turkish authorities have been engaged in a peace process with the PKK for months under which it says the group - and its extensions - must lay down weapons and disband to end a four-decade PKK insurgency in Turkey.
Footage from the protests showed participants, whom Ankara said supported Kurdish militants, trying to climb fenced walls along the Turkish-Syrian border in the Nusaybin-Qamishli region, while some burned or tore down Turkish flags in the area and chanted slogans.
Police used water cannon and pepper spray in attempts to disperse the crowds, amid scuffles with some protesters.
Justice Minister Yilmaz Tunc said on X that prosecutors had launched inquiries into the events, while the defence ministry said investigations were underway against PKK supporters trying to cross the border illegally at Nusaybin.
"With this attack in question, it is evident that dark forces aiming to sabotage the goal of a terror-free Turkey have once again come into play. These attempts will neither weaken the determination of our state nor harm the unity and solidarity of our nation," Burhanettin Duran, the Turkish presidency's communications director, said on X.
Omer Celik, spokesman for President Tayyip Erdogan's AK Party, vowed the "clearest and strongest response".
Turkey has since 2016 repeatedly sent forces into northern Syria to curb the gains of the SDF - which during Syria's 2011–24 civil war took control of more than a quarter of the country while fighting Islamic State with strong U.S. backing.
The SDF has said the peace process between the Turkish state and PKK does not apply to it.
(Writing by Tuvan Gumrukcu; editing by Ece Toksabay and Mark Heinrich)
