Airstrikes on rebel-held areas in the country’s northwestern city of Idlib killed 25 people , a monitor group reported.
The airstrikes targeted several areas in the countryside of Idlib, said the Syrian Observatory for Human Rights.
The London-based watchdog said the death toll could likely rise due to a large number of critically wounded people.
The Observatory also said that five people were killed and 15 others wounded on Tuesday by rebel shelling on the Shiite towns of Kafraya and Foa in Idlib countryside.
On Sunday, at least 34 people were killed by similar airstrikes in Idlib, according to the watchdog.
Much of Idlib has fallen to the rebels over the past year, except two Shiite towns loyal to the government.
The rebels who are fleeing or evacuating areas under their control in the capital Damascus or the northern city of Aleppo were all headed toward Idlib, making the province increasingly heavy with armed militants