A car bomb struck a security checkpoint near the headquarters of Syria's ruling Baath party and the Russian Embassy in the capital Damascus on Thursday, leaving smashed and burning cars on a main thoroughfare and at least four dead bodies lying in a nearby park, according to witnesses and opposition activists.
Syrian state TV also reported the blast in the central Mazraa neighborhood, calling it a "terrorist" attack by a suicide bomber on a heavily populated area near a mosque, a hospital, a bus station and a school. It said at least four children were among the wounded.
The state news agency published photos of two dead bodies lying in the street.
The pro-regime TV station Al-Ikhbariya showed images of what appeared to be at least four dead bodies on the ground and cars on fire. The footage shows firefighters trying to douse cars on fire and lifeless and dismembered bodies lying on the grass of a public garden.
The Britain-based activist group Syrian Observatory for Human Rights said the blast caused tens of dead and wounded.
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Eyewitnesses at the scene said a car had exploded at a security checkpoint between the Russian Embassy and the central headquarters of the ruling Baath party of President Bashar Assad.
"It was huge. Everything in the shop turned upside down," one local resident said. He said three of his employees were injured by flying glass that killed a young girl who was walking by when the blast hit.
"I pulled her inside the shop but she was almost gone. We couldn't save her. She was hit in the stomach and head," he said, speaking on condition of anonymity for fear of retribution for speaking with foreign media.
Ambulances rushed to the scene of the blast, which shattered windows and sent up a huge cloud of smoke visible throughout much of the city, witnesses said.
Russia's state owned RIA Novosti news agency quoted a Russian Embassy official as saying the Embassy building had been damaged in the blast but no one was hurt.
The blast followed two mortar attacks in as many days on the capital. On Wednesday, two mortar shells exploded next to a soccer stadium in Damascus, killing one player. The day before, two mortar shells blew up near one of Assad's three palaces in the city, causing only material damage.
Not long after the first blast Thursday, a security official reported a second blast in the capital's northeastern Barzeh neighborhood. He had no other information and spoke on condition of anonymity because he was not authorized to brief the media.
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The Observatory, which relies on a network of anti-regime activists inside Syria, said two car bombs had exploded near security centers in Barzeh, followed by intense clashes between rebels and security forces.
Damascus has so far mostly avoided the large-scale violence that has destroyed other Syrian cities, though deadly car bombings have targeted government buildings in the capital.
In May 2012, twin car bombs exploded outside a military intelligence building, killing 55 people in the deadliest attack against a regime target in the capital since the uprising began 23 months ago.
And in July, rebels detonated explosives inside a high-level crisis meeting in Damascus that killed four top regime officials, including Assad's brother-in-law and the defense minister.
Syria's conflict began in March 2011 with political protests against the government and has since evolved into a civil war between Assad's regime and hundreds of rebel groups seeking to topple it. The U.N. says some 70,000 people have been killed in the conflict so far.