Assad regime, Russia intensify attacks on rebel-held northwestern Syria
The attacks targeted villages and towns in northern Hama and southern Idlib – areas which fall within a buffer zone agreed in September between Russia and Turkey.
Jets dropped barrel bombs, killing at least 15 civilians and injuring dozens, Reuters reported rescuers in Idlib as saying.
Earlier this week Washington warned violence in the buffer zone "will result in the destabilisation of the region".
Idlib is under the control of a former al-Qaeda affiliate in one of the last areas that President Bashar al-Assad has not taken back in his ruthless, Russian-backed campaign to crush a popular uprising against his rule.
Russia and Turkey, which back Syria's rebels, in September agreed to a buffer zone to prevent a potentially devastating offensive in Idlib and nearby regions which are home to some three million people.
But the Syrian Observatory for Human Rights on Friday reported Russian airstrikes in two towns that killed 10 people, including a boy and a girl.
The monitor also blamed Moscow and Damascus for shelling a medical centre, which the UN humanitarian office called "completely unacceptable."
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