A fourth member of President Bashar Assad's inner circle, national security chief Gen. Hisham Ikhtiyar, died of wounds he suffered in Wednesday's bomb blast, which went off during a high level security meeting in Damascus, the government announced.
The bombing has been a resounding blow to Assad, killing his defense minister and his influential brother-in-law along with another security official, all central to directing the crackdown on the uprising against his rule.
The blast, six days of sustained fighting in neighborhoods across the heart of the capital and the fall of several border posts into rebel hands have pointed to the unraveling of Assad's grip on power amid an uprising that began in March 2011 with peaceful protests inspired by the Arab Spring but became increasingly militarized as the opposition took up arms.
Regime troops regained control of the district of Midan in the southern part of Damascus on Friday and eagerly took journalists on a tour to prove it. But rebels launched new fighting in several other districts of the capital, activists said.
The fighting came as Muslims around much of the world began marking Islam's annual Ramadan fast, abstaining from food or drink from sunrise to sunset. In a sign of the increasing sectarian split in Syria, the mainly Sunni opposition said it was starting the fast on Friday, along with Saudi Arabia and most Sunni-led Arab nations. The regime, meanwhile, said it would begin Saturday, as is its ally, Shiite-led Iran.
Battles involving troops bringing in tanks, helicopters and mortars have turned parts of Damascus into combat zones and sent thousands of Syrian families packed in cars streaming across the border into neighboring Lebanon.
"Our heroic forces have completely cleansed the Midan area of the terrorist mercenaries," state TV announced, employing the term used by authorities to refer to rebels. It said authorities seized large quantities of weapons including machine guns, explosive belts, rocket-propelled grenades and communications equipment.
Damascus activist Khaled al-Shami, contacted via Skype, said rebels carried out a "tactical" retreat early Friday to spare civilians further shelling after five days of intense clashes between opposition fighters and regime forces.
But in an indication of the volatile security situation, the government took local journalists for the trip to Midan inside two armored personal carriers Friday.
An Associated Press reporter on the trip saw scenes of destruction, including dozens of damaged or charred cars, stores with shattered windows. "The Mosque of the Free," read graffiti scrawled on the outer wall of the local Saeed Bin Zeid Mosque, apparently by opposition supporters who held sway in the neighborhood for days.
The corpses of at least six young men lay on the street. One of them, near the mosque, appeared to have been shot in the chest. Others were bearded and dressed in black with axes next to them. Garbage littered the streets, shops were closed and the streets were almost deserted.
But rebels continued to strike elsewhere in the capital Friday. Rebels attacked a police station on Khaled bin Waleed Street, where heavy fighting was going on, the Britain-based Syrian Observatory for Human Rights said. Clashes were also reported in the northern Barzeh and Rukneddine districts.
Details on the fighting were not immediately available.
A Syria-based activist who goes by the name of Bashir al-Dimashqi said the rebels in Damascus were staging hit and run attacks and striking at security targets as opposed to controlling areas.
"Their strategy is to paralyze public institutions and chip away at the regime," he said.
Activists reported that 310 people were killed in violence nationwide Thursday, making it the single deadliest day of fighting since the revolt began.
The toll included 93 government troops, the Syrian Observatory said. Another activist group, the Local Coordination Committees said 217 civilians were killed Thursday.
The figures could not be independently verified because of severe restrictions on journalists in Syria.
Also Friday, the United Nations Security Council voted to extend the mission of some 300 unarmed observers in Syria for 30 days.
The team was meant to oversee a cease-fire that was supposed to begin in mid-April but never took hold. In recent weeks, violence has kept the observers largely confined to their hotels.
The vote extends the mission, which was set to expire Friday, for 30 days, though it can be extended if Syrian troops stop using heavy weapons in populated areas and the overall level of violence drops.
On Thursday, Russia and China vetoed a resolution backed by Western nations that would have imposed new sanctions on Assad's regime.
Besides the fighting in Damascus Friday, about a half-dozen rebels took over a Syrian border crossing near the Iraqi town of Qaim on Thursday, said Iraqi army Brig. General Qassim al-Dulaimi. There are four major border posts with Iraq.
Rebels overtook a Syrian army outpost near the Syrian-Iraq border after clashes that killed 21 Syrian soldiers, he added.
In addition, amateur video posted online showed rebels taking over the Bab al-Hawa border crossing with Turkey, where they stomped on portraits of Assad. The Associated Press could not independently verify the video because the government bars most media from working independently in the country.
A Turkish official based in Reyhanli, on the Turkish side of the border gate of Bab al-Hawa, confirmed that the rebels had taken control of the frontier crossing, but had no information on the latest situation over on the Syrian side.
Another official said Turkey has temporarily closed the border gate "for security reasons." Both spoke on condition of anonymity in line with government rules that bar civil servants from speaking to journalists without authorization.
The Damascus fighting and Wednesday's bomb blast have shown increased capabilities by Syria's rebels, made up of military defectors and protesters who took up arms. They have managed to launch operations in the capital before, but never carried out such sustained fighting.
In the bombing, they succeeded in slipping an explosive into an inner sanctum of the regime.
The funerals of the first three victims of the blast — Defense Minister Dawoud Rajha, Deputy Defense Minister Gen. Assef Shawkat and Hassan Turkmani, a former defense minister — were held Friday in Syria amid "official presence," state TV reported.
The state news agency said Vice-President Farouq al-Sharaa and Gen. Fahd al-Freij, the new defense minister, laid wreaths on the men's coffins.
Assad did not attend and has only appeared in a brief, soundless video clip aired on state TV since the bomb attack.
Shawkat was the husband of Assad's sister and a major adviser. Rajha was the highest-ranking Christian in Assad's leadership, which is dominated by members of his own Alawite sect, an offshoot of Shiism.
Syria's Al-Dunia TV later showed brief images of Rajha's funeral at a church in Damascus. It showed the coffin, wrapped in a red, white and black Syrian flag surrounded by clapping crowds as women dressed in black cried in mourning.