A huge bomb blast echoes through what is purportedly the Syrian capital -- captured by an amateur videographer and uploaded to a social media website.

It's one of two blasts that went off in Damascus early Thursday morning, killing scores and wounding more than 100 others.

Syrian state television said the explosions, one of which left a giant crater surrounded by destroyed cars and damaged buildings, were the work of "terrorists".

The British-based Syrian Observatory for Human Rights said at least one of the explosions was caused by a car bomb, and that the target was Government intelligence buildings.

The blasts caused limited damage to the nearby Palestine Branch Military Intelligence complex - one of the country's most feared secret police organisations.

U.N. ceasefire monitors visited the site shortly after the explosions went off - and were quickly surrounded by supporters of Syrian President Bashar al-Assad.

According to the United Nations, at least 9,000 people have been killed since a popular revolt began over a year ago.

Travis Brecher, Reuters