By Erika Solomon
BEIRUT | Sun Dec 9, 2012 10:55am EST
(Reuters) - Syrian rebels backed by radical Islamists captured a northern regimental command center of President Bashar al-Assad's army, activists said on Sunday, as Russia dismissed speculation that it is preparing for its ally's possible exit from power.
Assad's forces hammered rebel units on the outskirts of Damascus as they tried to drive back opposition fighters rebels seeking to advance toward the embattled leader's seat of power.
Rebels have made a series of advances in recent weeks, partly due to help from radicals such as Jabhat al-Nusra, a group linked to Al Qaeda in Iraq which has been excluded from a newly-formed rebel military command.
The Syrian Observatory for Human Rights said Jabhat al-Nusra, which has called for the creation of an Islamic state in Syria, had participated in capturing the command center of the army's 111th regiment in the north of the country. It said around five soldiers were captured, while the commanding officer and some 140 of his men fled to another army site nearby.