Russian warplanes hit Hama for the first time since a truce brought relative calm to the region in March.
Russian air raids target NW Syria for first time in three months
Russian air raids have targeted Syria's last major rebel-held enclave in the country's northwest for the first time since a March ceasefire came into effect, Syria's Civil Defence and a war monitor said.
The attacks, which came in waves on Tuesday evening and at dawn on Wednesday, hit an area where the boundaries of Hama, Idlib and Latakia provinces meet, the the Syrian Observatory for Human Rights (SOHR) said.
The Syrian Civil Defence, also known as the White Helmets - a volunteer search-and-rescue group that operates in rebel-held parts of Syria - confirmed that air raids hit Sahl al-Ghab, an area in western Hama.
No injuries were reported but opposition activists in the area said the air raids forced hundreds of people to flee their homes to safer areas further north.
The attacks on and near Idlib province were the first to be conducted by Russian planes since a truce brought relative calm to the volatile region in early March.
The ceasefire, brokered by opposition backer Turkey and Syrian government ally Russia, halted a bloody three-month air and ground campaign that killed at least 500 civilians.
It also created the worst displacement crisis of the war in Syria, now in its 10th year. Nearly one million people were forced to flee, with many seeking shelter in the already overcrowded camps near the sealed border with Turkey.
Some 840,000 of the nearly one million remain displaced, while approximately 120,000 have returned to their home communities since the ceasefire went into force, according to the United Nations.
Home to some three million people, the Idlib region of the northwest is controlled by Hay'et Tahrir al-Sham (HTS), a former al-Qaeda affiliate, and other rebel groups.
The SOHR said the latest attacks were intended to push opposition fighters away from the key M4 highway in northern Syria, where Turkish and Russian forces often conduct joint patrols as part of the truce agreement.
They were also intended to push HTS and its allies further away from the Sahl al-Ghab area, where government and Russian forces are present, it added.
After holding barely a fifth of the country five years ago, Russian intervention has helped the government reclaim control of more than 70 percent of Syria.
In the northwest, HTS and its allies control about half of Idlib province and slivers of territory in the neighbouring provinces of Hama, Latakia and Aleppo.
In recent years, Moscow and Ankara have become the main power-brokers in Syria, shattered by a civil war since 2011.
The war in Syria has killed more than 380,000 people and displaced nearly half of the country's prewar population.