The Local Coordination Committees says the attack on the town of Ihsim killed 17 people and wounded dozens.
The Britain-based Syrian Observatory for Human Rights said 18 were killed, including four members of the same family.
Syrian airstrikes carried out by warplanes and helicopters have killed thousands of people in recent years. The U.N. says that Syria's civil war has killed more than 220,000 people and wounded at least a million since the conflict began in March 2011.
