The United Nations' top aid official on Thursday demanded an immediate investigation into the killing of displaced civilians in a camp hit by air strikes in northern Syria.
"If this obscene attack is found to be a deliberate targeting of a civilian structure, it could amount to a war crime," said Stephen O'Brien, the UN under-secretary general for humanitarian affairs.
At least 28 civilians including women and children were killed in the air strikes at the camp near Sarmada in Idlib province, which is controlled by the Al-Qaeda-linked Al-Nusra Front and rebel allies.
"I am horrified and sickened by the news of civilians killed today by air strikes that hit two settlements where displaced people had sought sanctuary," O'Brien said in a statement.
Thousands of Syrians have fled fighting in the northern province over the last weeks, and camps for the displaced have been set up along the Turkish border.
The air strikes come after an intense diplomatic push to revive a landmark ceasefire and salvage peace efforts to end Syria's five-year conflict.
The war in Syria has killed more than 270,000 people and displaced millions since it started after the brutal crackdown of anti-government protests in 2011.
