The Syrian Observatory for Human Rights believed the strike was carried out by the American coalition.
Hundreds of civilians were killed in an air strike delivered by the US-led coalition on the town of Mansura in the Raqqa province in north Syria, the news agency Anadolu reported on Wednesday.
According to the agency’s data, the air strike targeted a school housing displaced people.
Meanwhile a group of activists а «Raqqa is Being Slaughtered Silently» reported that the fate of the 50 families who were in the building was unknown.
There was no immediate comment from the coalition, but it has said there were 19 strikes near Raqqa on Monday, including three that destroyed Islamic State headquarters.
The Air Force of the US-led coalition is providing air support for Arab-Kurdish formations from the Syrian Democratic Forces (SDF) advancing on Raqqa. The operation codenamed Euphrates Anger against the Islamic State’s main stronghold in Syria began in November last year. It involves 30,000 fighters.