Two large explosions have shaken the centre of Syria's capital Damascus, near the military general staff headquarters.
The blasts happened just before 07:00 local time (04:00 GMT) in an area dominated by government buildings,
A BBC journalist in the city reported hearing brief bursts of small arms fire coming from the area.
Thick smoke is now rising from buildings targeted. It is unclear what caused the explosions.
State television, whose headquarters is close to where the blast happened, described the blasts as a terrorist attack.
Witnesses said the second explosion had hit the main building of the military compound, and it was on fire.
State media said only that fires had broken out near the military headquarters.
No rebel group has said it carried out an attack.
Ambulances rushed to the scene of the explosions, amid reports of injuries and a continuing gun battle between rebels and government forces.
The blasts erupted close to Umayyad Square, one of the main areas in central Damascus. Traffic in the area has reportedly been brought to a standstill.
On Tuesday, anti-government rebels blew up a school building in Damascus that they said was being used for military training.