Rebels took control of an air defense brigade in Homs, the Syrian Observatory for Human Rights reported Sunday.
Syrian President Bashar Assad's forces later bombarded the nearby village of al-Ghento. Most of the brigade defected and retreated with the rebels before the bombardment began, the British-based watchdog reported.
Assad's forces killed at least 35 people in the attack on the Homs province, which was one of the biggest bombardments since a failed UN-mandated ceasefire in April, opposition activists said.
They said the Syrian army used artillery, mortars and rockets to hit opposition strongholds in the city of Homs and the towns of Qusair, Talbiseh and Rastan in central Syria.