The protests took a violent turn when hundreds of demonstrators marched near checkpoints around the city a day after one civilian was killed in protests that swept the area demanding the end of Kurdish minority rule over a mainly Arab tribal population.
The unrest was the bloodiest to sweep the mainly Arab city since it was captured five years ago by the Syrian Democratic Forces (SDF), a U.S. backed militia force spearheaded by the Kurdish YPG after it drove out Islamic State.
Resentment against SDF rule has grown in north and eastern Syria among the predominately Arab population, residents and tribal elders said. Many object to compulsory conscription of young men and discrimination in top leadership layers.
The fate of thousands imprisoned in their jails has also been a major bone of contention, according to residents and tribal figures.
According to Reuters SDF officials imposed a curfew on the city and beefed up checkpoints around its main routes after many shops heeded a call for a general strike.
There were also attempts to mediate with local tribal leaders to calm the unrest that the SDF blamed the YPG's erstwhile enemy Turkey and agents of the Syrian government were behind to destabilize their rule.
The Kurdish-led SDF deny its local administration discriminates against Arabs and say their policies seek to redress years of injustice by Syria's Arab nationalist Baath rulers whom they say had for decades denied them equal citizenship rights as Syrians.
Some 30 km from the Turkish border, Manbij occupies a critical spot in the map of the Syrian conflict, near the junction of three separate blocks of territory that form spheres of Syrian, Turkish and U.S. influence.
Manbij's capture by the mainly Kurdish forces with crucial help from the U.S. coalition has angered neighboring Turkey which views the influence wielded by the YPG in northern Syria as a national security threat.
Ankara has criticized Washington for not adhering to roadmap endorsed between them in June 2018 for the withdrawal of Kurdish militants from Manbij and to jointly secure the city.
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