Demonstrators lift banners protesting Turkish strikes and supporting women fighters during a rally on the International Day for the Elimination of Violence Against Women at the Free Woman square in the Kurdish-majority northern Syrian city of Kobane, on November 25, 2022. AFP
The Kurdish-led Syrian Democratic Forces (SDF) on Sunday arrested the chief of the Deir Ezzor Military Council, a local Arab armed group affiliated with the Kurdish force, triggering clashes which have since left dozens dead.
"The Deir Ezzor Military Council and the Internal Security Forces announce a curfew... from 0500 AM (0200 GMT) on September 2, for 48 hours," the SDF said in a statement.
The statement said armed groups affiliated with the Damascus government security services, as well as Islamic State group cells, were attempting to "cause civil strife in the region and lure civilians into their dirty plans".
Rami Abdel Rahman, who heads the Syrian Observatory for Human Rights war monitor, told AFP that Iran-backed Arab fighters had taken advantage of the clashes to cross over from the government-held part of the province into two Kurdish-controlled villages.
The fighters had clashed with local Kurdish-led forces, with their leader publishing a video urging Arab tribes to turn against Kurdish authorities.
The United States called earlier on Friday on "all parties to de-escalate and peacefully resolve the situation".
"The violence in northeast Syria must cease," said the US military's Operation Inherent Resolve, which supports the fight against remnants of IS.
In a statement late Thursday, the Operation urged a renewed focus on efforts to bring "peace and stability in northeast Syria, free from the threat of Daesh," another name for IS.
"We remain focused on working with the Syrian Democratic Forces to ensure the enduring defeat of Daesh, in support of regional security and stability. Distractions from this critical work create instability and increase the risk of Daesh resurgence."
The US-backed SDF spearheaded the offensive that defeated the IS group's self-declared caliphate in Syria in 2019. It controls a semi-autonomous Kurdish zone in Syria's northeast, including large parts of the Deir Ezzor province.
The reasons for the arrest of the head of the Deir Ezzor Military Council, Ahmad al-Khabil, also known as Abu Khawla, have not been disclosed.
But the Observatory and a local activist told AFP that he was known to run highly lucrative smuggling activities.
The Britain-based Observatory told AFP 54 people have been killed since the clashes broke out Sunday, mostly supporters of Khabil and SDF members, but also six civilians.
The Kurds administer the area through local civilian and military councils in an effort to stave off Arab discontent.
Some of the tribes had supported IS during its bloody reign, according to the Observatory, which relies on a vast network of sources inside Syria.
Syria's war has killed more than half a million people since it broke out in 2011 and quickly escalated into a deadly conflict that pulled in foreign powers and jihadists insurgents.