At least 14 civilians have been killed and several others wounded in a series of barrel-bomb attacks on rebel-held areas near Damascus.
Syrian government air strikes targeted the town of Wadi Barada, northwest of the capital on Monday, injuring dozens of people, including several children, activists said.
According to videos posted on social media by opposition groups, the Syrian regime intensified its assault on the town.
The White Helmets, a team rescuing people from bombed-out houses, said a number of people were trapped under the rubble following the heavy bombardment.
Barrel bombs are typically constructed from large oil drums and filled with explosives, nails and scrap metal.
a source reporting from Gaziantep on the Turkish side of the Turkey-Syria border, said the Syrian regime was in the third day of an offensive against Jaish al-Islam, which controls Wadi Barada and is one of the most powerful groups fighting President Bashar al-Assad’s forces.
On Friday, the Syrian army and the Lebanese armed group Hezbollah, launched an operation to retake Wadi Barada, after accusing the rebels of contaminating drinking water at a spring with diesel.
The Wadi Barada valley, a mountainous area near the Lebanese border, has been under siege since 2014 with food, water and electricity all in short supply.
According to a report published earlier this year, more than one million Syrians are believed to be trapped in 46 communities across the country.
The Syrian civil war started as a largely unarmed uprising against Assad in March 2011, but quickly developed into a full-on armed conflict.
Staffan de Mistura, the UN special envoy to Syria, estimated in April that more than 400,000 Syrians had been killed since 2011.
Calculating a precise death toll is impossible, partially owing to the forced disappearances of tens of thousands of Syrians whose fates remain unknown.
Almost 11 million Syrians – half the country’s pre-war population – have been displaced from their homes.