The Syrian army aided by Russian warplanes shelled rebel-held towns in northwestern Syria in the most extensive bombardment in weeks against the last remaining rebel bastion in the country, rebels, rescuers and residents said on Wednesday.
Rebels who have fought to topple President Bashar Assad for eight years are now largely confined to the enclave in the northwest near the Turkish border. Around 4 million people now live there, including hundreds of thousands of opponents of Assad who fled there from other parts of the country.
The enclave is protected by a "de-escalation zone" agreement brokered last year by Assad's main international backers Russia and Iran, and Turkey, which has supported the rebels in the past and has sent troops to monitor the truce.