DAMASCUS, Dec. 25 (Xinhua) -- The Kurdish-led Syrian Democratic Forces (SDF) rounded up 262 Islamic State (IS) militants who tried to flee among civilians out of their last stronghold in eastern Syria, a war monitor reported Tuesday.
The civilians tipped off the SDF militia about the IS militants who were trying to leave the eastern bank of the Euphrates River in the eastern countryside of Deir al-Zour Province, according to the Syrian Observatory for Human Rights.
Around 5,500 civilians have fled the last IS bastion in the eastern Euphrates since the United States declared its decision to withdraw from Syria last week, the London-based watchdog said.
The incident comes as the SDF is advancing against the IS in the eastern Euphrates, the Observatory added.
The U.S.-backed SDF fighters launched an offensive against the IS in the eastern countryside of Deir al-Zour in September, and has continued its anti-IS battles despite the threats of a Turkish campaign that would target the Kurdish militia.
The SDF militants are regarded by Ankara as terrorists over their links with the Kurdistan Workers' Party (PKK), which is listed as a terrorist organization by Turkey, the United States and the EU.
The Observatory said the Turkish forces continue to send reinforcements to the frontline with the SDF near the Kurdish-controlled city of Manbij in the northern countryside of Aleppo.
The Kurdish militia forces have criticized the U.S. decision to withdraw from Syria and called it a "stab in the back."