A Kurdish source, speaking on condition of anonymity, told Sputnik news agency that Daesh militants killed 36 civilians, among them women, children and senior civilians, as they mounted an assault against the village of al-Ghandoura, which lies northeast of the city of Manbij and is located nearly 450 kilometers (279 miles) north of the capital, Damascus, on Friday.
The source added that Daesh terrorists were clad in the uniform of the Syrian Democratic Forces (SDF) militiamen to carry out the heinous act of terror.
Residents of Ghandoura greeted the terrorists thinking they were SDF fighters. The Daesh extremists then killed everybody whom they met.
The unnamed Kurdish source went on to say that a similar incident took place in a village north of Manbij on June 6, without specifying the number of the victims.
On May 14, at least 20 people, most of them Syrian soldiers and allied fighters from popular defense groups, were killed when Daesh terrorists attacked al-Assad hospital in the eastern Syrian city of Dayr al-Zawr.
The so-called Syrian Observatory for Human Rights said the attack came at the eastern entrance of the hospital and sparked clashes between government forces and Daesh militants.
The London-based monitoring group added that at least six militants from the Takfiri group were killed as well.
Syria has been gripped by a foreign-backed militancy since March 2011. According to United Nations Special Envoy for Syria Staffan de Mistura, over 400,000 people have been killed in the conflict.
A ceasefire brokered by the US and Russia went into effect on February 27 in Syria, but it does not apply to Daesh and al-Nusra Front terrorist groups.
The Syrian army has vowed to press ahead with its counter-terror operations and drive terrorists out of their major positions.