At least three key members of Syrian President Bashar al-Assad's inner circle were killed Wednesday in an unprecedented attack in the capital Damascus, state media reported, dealing a severe blow to the regime, DPA reported.
Defence minister Daoud Rajha; his influential deputy Assef Shawkat - al-Assad's brother-in-law; and assistant vice president Hassan Turkmani were killed in what state television described as a "terrorist explosion" at a national security building.
Interior Minister Mohammed Ibrahim al-Shaar was among those seriously wounded in the bombing, which took place as senior military and security officials were meeting inside the building in the district of Rawda, according to opposition activists.
"We have unconfirmed information that al-Assad's cousin, Hafez Makhlouf, who heads investigations at the intelligence agency, was also killed," said one activist.
The rebel Free Syrian Army (FSA) claimed responsibility for the attack. "Until now, we have confirmed information that the defence minister, his deputy and three other senior commanders were killed," FSA founder Riad al-Asaad told dpa by phone.
"The Free Syrian Army planted an explosive in the building in coordination with some collaborators inside," he added. "It is a crushing blow to the regime."
Activists claimed a bodyguard of a high-ranking official attending the meeting planted the bomb.
Within hours, al-Assad named Major General Fahd Jasim Frij as defence minister, the state news agency SANA reported, but the president made no statement on the attack.
Appearing on state television, Frij called on his soldiers to "stay steadfast" and protect the country from "terrorist attacks."
The blast took place as fierce clashes between the army and rebel fighters entered their fourth consecutive day in Damascus.
Fighting was reported in the central district of al-Midan, where rebel fighters are still holed up. The military was bombarding the district, said the opposition Syrian Observatory for Human Rights.
Rebel fighters had already announced Tuesday that the "greater battle" for Damascus had begun, and that they were using new tactics by launching simultaneous attacks in the capital.
Over the past few days, the rebels have launched their most daring attacks against the military in Damascus, bringing the conflict to al-Assad's doorstep and forcing the regime to deploy heavy armour in the capital.
"We expect this operation to plunge the regime into real confusion, while boosting the morale of the revolutionaries," the FSA's al-Asaad said.
At least 57 people were killed Wednesday across the country, the opposition said.
Meanwhile, the UN Security Council decided to postpone to Thursday its vote on renewing the mandate for the unarmed military observers in Syria, whose three-month term is due to expire.