The UK-based Syrian Observatory for Human Rights said 16 rebels were among the dead in the fighting in and around Dael. The town lies fewer than ten miles from the Jordanian border in Daraa province, where the uprising against president Bashar Assad’s regime began two years ago.
The rebel gains have coincided with what regional officials and military experts say is a sharp increase in weapons shipments to opposition fighters by Arab governments in co-ordination with the US in the hopes of readying a push into Mr Assad’s Damascus stronghold.
Although rebels control wide areas in northern Syria that border Turkey, the Jordanian frontier is about 60 miles from Damascus, or a third of the distance to the Turkish border.
The battle for Dael came as authorities ordered an investigation into a mortar attack on Damascus University that killed at least ten students on Thursday, state media said. The attack was the deadliest since a wave of mortar shells began hitting the capital last month.