US-led warplanes drop white phosphorus bombs in northeast Syria
The sources added that the aerial assaults also badly damaged residential buildings in the area.
The development came only a day after at least nine civilians lost their lives in US-led airstrikes against the town of Markadah, located nearly 100 kilometers south of the northeastern city of Hasakah.
Informed sources said two women and a six-member Iraqi family, who had escaped fighting in the northern Iraqi city of Mosul, were among the victims of the attacks.
The so-called Syrian Observatory for Human Rights reported on Saturday that more than 2,800 civilians had been killed in US-led airstrikes across Syria over the past three years.
The Britain-based monitoring group reported that 427 people, including 137 minors and 113 women, were killed in the aerial attacks between May 23 and June 23 this year.
The US-led air raids also resulted in the injury of hundreds of civilians, some of whom suffered permanent disabilities and had to have their limbs amputated.
The aerial raids caused massive destruction of residential buildings and civilian infrastructure as well.
The US-led coalition has been conducting airstrikes against what are said to be Daesh targets inside Syria since September 2014 without any authorization from the Damascus government or a UN mandate.
The military alliance has repeatedly been accused of targeting and killing civilians. It has also been largely incapable of achieving its declared goal of destroying Daesh.
The Syrian Ministry of Foreign Affairs and Expatriates, in two separate letters sent to UN Secretary General António Guterres and rotating President of the UN Security Council Amr Abdellatif Aboulatta on August 24, stated that the US-led coalition was perpetrating war crimes and crimes against humanity through aerial bombardment of residential neighborhoods.
The Syrian Foreign Ministry also stressed that the military alliance was using internationally-banned white phosphorus munitions in flagrant violation of international law and the Charter of the United Nations.