Air strikes against the Islamic State (IS) extremist group's stronghold of Raqqa in eastern Syria have killed dozens of people.
The Britain-based Syrian Observatory for Human Rights said that at least 39 people had been killed and dozens more wounded in the raids on Raqqa March 19.
An activist group with sources in Raqqa, called Raqqa Is Being Slaughtered Silently, said more than 40 had been killed.
The monitoring groups said it was not clear whether the strikes were by Syrian or Russian warplanes.
A cessation of hostilities in Syria took effect three weeks ago, reducing violence but not halting the fighting as peace talks take place in Geneva.
The cessation of hostilities deal does not include Al-Qaeda or IS militants.