First Turkish strikes on Syria's Kurdish zone in months
"A Turkish fighter jet has struck military positions of Syrian Democratic Forces (SDF) in Saida village in Ain Issa countryside... which caused loud explosions," the Syrian Observatory for Human Rights (SOHR) said.
This was the first aerial raid since "Operation Peace Spring", it added - an October 2019 military campaign launched by Ankara and its Syrian allies against the SDF in northern Syria.
That operation, interrupted after two accords negotiated by Ankara with first Washington, and then Moscow, allowed Turkey to to seize control of a "safe zone" inside Syria around 120 kilometres long and 32 kilometres deep.
The village of Ain Issa, however, remained in the hands of Kurdish forces.
The air strikes come the same day as "violent clashes" and "intensive rocket fire" on the frontlines of Ain Issa district between SDF forces and Turkish-backed factions, the SOHR said, adding there had been confirmed casualties.
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"Clashes between the two sides have been going on for the last 24 hours... Turkish forces have had difficulty advancing since the SDF destroyed a Turkish tank," the director of the SOHR, Rami Abdul Rahman, told AFP.
The Syrian Kurdish-led People's Protection Units, which form a vital component of the SDF, are considered by Turkey to be a "terrorist offshoot" of the outlawed Kurdistan Workers' Party.
But they have also been a key ally to the United States and others in the battle against the Islamic State group in Syria.
Agencies contributed to this report.