Syrian rebels bombed a military complex in Damascus yesterday, igniting a fire that gutted the army command headquarters.

The Free Syrian Army, the main force fighting to overthrow President Bashar al Assad, claimed responsibility for the attack, which it said left dozens dead.

But an armed forces statement said military leaders were unhurt, although four security guards were wounded in the blasts.

It was the biggest attack since July 18, when a blast killed several security officials, including Mr Assad's brother-in-law, the defence and interior ministers.

That attack paved the way for a rebel advance into the capital, although they have since been pushed back to the outskirts.

Internet footage of yesterday's fire at the General Staff Command Building in Umayad Square showed flames engulfing its upper floors, indicating explosives were planted inside.

The blast also left a deep crater in the ground, apparently where the explosive-laden car blew up.

"All our colleagues in the military leadership, the army staff command and the Defence Ministry are unhurt," Information Minister Omran Zoabi said.

Security forces were chasing "armed terrorists" – a term the authorities use to refer to insurgents waging war to oust Assad.

"It's a terrorist act, close to an important site, that's true. But they failed to achieve their goal," he said.

Activist Sami al Shami said the main explosions were caused by a suicide car bomb and second car loaded with explosives on the perimeter of the complex.

"The fighters went inside and clashed with security, while some men started to torch the building," he said.

"There must be several security forces dead, there's no way the rebels could have made it in that far without killing any security forces," he said.

A correspondent for Iran's English-language Press TV was shot dead by a rebel sniper, and its Damascus bureau chief was wounded while they covered Wednesday's explosions, Press TV said.