Airstrikes on a camp housing Syrians displaced by the five-year war in the country killed at least 28 people near the Turkish border on Thursday. The attack was carried out on the Kamouna camp in the northern Idlib province, and hit at around 6.20pm local time, according to the Syria Civil Defense volunteer organization.
The monitoring group Syrian Observatory for Human Rights (SOHR) said the dead included women and children, and that the death toll from the airstrikes is likely to rise.
On Friday, the UN High Commissioner for Human Rights described the attack as "despicable."
"Given these tent settlements have been in these locations for several weeks, and can be clearly viewed from the air, it is extremely unlikely that these murderous attacks were an accident. It is far more likely they were deliberate and amount to a war crime," Zeid Ra'ad Al Hussein said.
A video posted on social media by the Syrian Civil Defense showed rescue workers attempting to put out fires which still burned among charred tent frames, pitched in a muddy field. White smoke billowed from smoldering ashes, and a burned and bloodied torso could be seen in the footage.
Warning: Graphic footage below.
(Photo via Syrian Civil Defense)
"There were two aerial strikes that hit this makeshift camp for refugees who have taken refuge from fighting in southern Aleppo and Palmyra," said Abu Ibrahim al-Sarmadi, an activist from the nearby town of Atmeh who spoke to people near the camp.
Nidal Abdul Qader, an opposition civilian aid official who lives near the camp, said around 50 tents and a school had burned down.
On Friday, the Syrian military denied that its warplanes had conducted the airstrikes.
"There is no truth to reports… about the Syrian air force targeting a camp for the displaced in the Idlib countryside," it said in a statement carried by state media.
Meanwhile, United Nations aid chief Stephen O'Brien said he was horrified and sickened by what had happened and called for an investigation.
"If this obscene attack is found to be a deliberate targeting of a civilian structure, it could amount to a war crime," O'Brien said in a statement. "I call for an immediate, impartial, and independent investigation into this deadly incident."
He also said international law requires warring parties to protect civilians and avoid places they are living. "Modern military technology means that there is little room for error," he said.
The internally displaced person (IDP) camp lies about 20 miles west of Aleppo, where a cessation of hostilities brokered by Russia and the US had brought a measure of relief on Thursday.
But fighting continued nearby, while Syrian President Bashar al-Assad said in a telegram to Russian President Vladimir Putin his army would not accept anything less than "attaining final victory" and "crushing the aggression" by rebels in the region, according to state media.
Russia also blocked a British-drafted UN Security Council statement, which would have condemned the surge in violence in Aleppo and attacks against civilians.
"There is one country that could not agree it and it's Russia," Britain's UN Ambassador Matthew Rycroft told reporters. "That does speak volumes about their support for protection of the Assad regime."
In the east of the country, Islamic State militants captured the Shaer gas field, their first gain in the Palmyra desert area since they lost the ancient city in March, according to rebel sources and a monitor.
The SOHR and a local resident reported rebel shelling of the government-held side of Aleppo, which was Syria's commercial hub and largest city before the war.
But a resident of the rebel-held eastern part of the city said that although warplanes flew overnight, there were none of the intense raids seen during the past 10 days. People in several districts ventured onto the streets.
A rebel source also said that despite intermittent firing across the city's front lines, fighting had subsided and no army shelling of residential areas had been heard.
Rebels also said government helicopters dropped barrel bombs on rebel-held Dahyat al-Rashdeen al Junobi, northwest of Aleppo, and near the Jamiyat al Zahraa area, which saw a rebel ground assault pushed back on Wednesday.
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