The bombing of a high-level security meeting Wednesday in Damascus claimed three of Syrian President Bashar Assads inner circle.
The incident and intensified fighting in the capital have caused some analysts to wonder if the end is near for the Syrian regime.
Killed were Defense Minister Dawoud Rahja; the presidents brother-in-law and confidant Assef Shawkat, and Interior Minister Hassan Turkmani.
Each of the three were key figures. Mr. Turkmani led the governments response to the uprising and is accused by regime opponents of ordering the torture of anti-Assad activists.
The Free Syrian Army has fought regime forces in the capital in recent days; those clashes have intensified. The bomb attack indicates that the presidents foes likely have informers close to the regime, said Paul Salem of the Carnegie Middle East Center.
In the last couple of weeks, there have been dramatic events that have indicated a meltdown, Mr. Salem told USA Today. Most significant has been the fighting in Damascus, which demonstrates a massive loss of control by the regime.
The bombing at the National Security building has boosted the uprising, whose supporters Syrian forces have attacked for the past 17 months, killing Syrian civilians and rebel troops alike. Some 17,000 people have lost their lives.
Danielle Pletka of the American Enterprise Institute said events show President Assad cant last and that it may be the beginning of the end.
From the start of the Arab Spring in Syria, the Assad regime has met the protests and calls for reform with deadly force. It has not worked because the Syrian people persisted despite the dangers.