Syrian government air strikes on an opposition-held town killed at least 15 civilians in the southern province of Daraa on Monday, a monitoring group said.
"The death toll from four regime air strikes on Jassem in Daraa province has risen to 15 civilians, while more than 25 others were wounded," the Syrian Observatory for Human Rights said.
The strikes come as a major rebel offensive has been underway in southern Syria for months.
"As usual, the regime is striking populated areas in order to make civilian supporters of opposition fighters turn against them," Observatory director Rami Abdel Rahman said.
While rebels have suffered a spate of defeats at the hands of government forces, they still have the upper hand in Daraa.
"Opposition fighters are making steady progress in Daraa province. The vast majority of the west of the province has completely fallen out of government control, and that is where Jassem is located," Abdel Rahman said.
Rebels in the area benefit from "the fact that supply lines from Jordan are still open," he added.
The involvement of experienced fighters of Syria's Al Qaeda affiliate, the Al-Nusra Front, has also helped the rebels win territory in Daraa.
Elsewhere, air strikes on the besieged, rebel-held town of Douma east of Damascus killed at least three civilians, the Observatory said.
An AFP photographer in Douma said the strikes hit residential areas and that most of the wounded were children.
The Syrian conflict began as a peaceful uprising in March 2011 but rapidly escalated into armed rebellion as the government unleashed a brutal crackdown.
More than 200,000 people have been killed, and nearly half of the population has fled their homes.