Two rebel Syrian groups claimed responsibility for an explosion in Damascus on Wednesday that killed several top state officials, hailing it as a successful strike at the heart of the government.
Syrian state TV said a "terrorist bombing" had killed defence minister Daoud Rajha as well as Assef Shawkat, President Bashar al-Assad's brother-in-law and the deputy defence minister. Several others were wounded, it said.
Two rebel groups claimed they carried out the attack, calling it a victory against Assad's inner circle, once seen as an impenetrable force.
Liwa al-Islam, an Islamist rebel group whose name means "The Brigade of Islam", said in a statement on its Facebook page that it had "targeted the cell called the crisis control room in the capital of Damascus."
"We happily inform the people of Syria and especially the people of the capital that the National Security Bureau, which includes what is called the crisis management cell, has been targeted with an explosive device by the Sayyed al-Shuhada brigade of Liwa al-Islam," the statement read.
"Several regime pillars have been killed," it added.
The Free Syrian Army also claimed responsibility for the attack, according to Qassim Saadedine, a spokesman. "This is the volcano we talked about, we have just started," he said.
A security source in Syria told Reuters that a bodyguard for the president's inner circle had detonated explosives at a meeting of ministers and President Assad's top security and military officials.
A spokesman for Liwa al-Islam confirmed the claim by telephone but denied that it was a suicide attack.
"Yes we did the attack but there was no suicide bomber," said the man, who asked to be identified as Abu Ammar. "Our men managed to plant improvised explosives in the building for the meeting. We had been planning this for over a month."
Minister of Interior Mohammad Ibrahim al-Shaar was wounded but stable, and intelligence chief Hisham Bekhtyar was in surgery, according to a Syrian security source who spoke to Reuters.
Syria has been mired in a bloody 16-month-old conflict as rebels struggle to end four decades of Assad family rule.
Residents in the capital said they did not hear a sound from the lethal blast in the city centre, or see any traces of smoke.