Syrian security forces have killed two gunmen after the group detonated a car bomb in the diplomatic quarter of Damascus.
A Syrian policeman and a woman bystander were also killed in the clash last night in the suburb of Mazze, SANA quoted an interior ministry official as saying.
Security forces later raided a building in Mazze used by the group and found a cache of arms and explosives, state-run Syrian television said.
The ministry official told SANA security forces clashed with the gunmen in the well-guarded diplomatic quarter after the car bomb exploded, badly damaging an uninhabited building that formerly housed U.N. offices and setting fire to it.
"Group members hid in a car and threw hand grenades at security forces," SANA quoted the official as saying. Security forces surrounded the car and sounds of the ensuing gunbattle echoed through the streets of the Syrian capital.
Witnesses said the four-storey former UN building near the Canadian embassy was gutted by the bomb, its windows blown out, and nearby cars were damaged and shop fronts shattered.
State TV later showed footage of the arms cache, which included rocket-propelled grenades, gas cylinders and bags of yellow powder. It said the depot was used by the group that set off the car bomb.
Syria has seen little violence under the tight security maintained by the government of Bashar al-Assad after he took over from his father in 2000, but there was fighting between security forces and restive Syrian Kurds last month.
The United States has accused Syria of sheltering "terrorists" and not doing enough to stop foreign fighters infiltrating from its territory into neighbouring Iraq.
Syria says it has done its utmost to control the border and has helped the United States in its "war against terror".