Russian airstrikes have killed 36 civilians in Syria's north-western Idlib province on Monday, the Syrian Observatory for Human Rights said.
"There are children among the killed," the head of the observatory, Rami Abdel Rahman, told dpa.
"This is the highest civilian toll since Idlib was declared a de-escalation zone," he added.
On September 15, Russia, Turkey and Iran agreed to create a so-called "de-escalation zone" in Idlib, an area under the control of opposition forces in northern Syria.
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