Syrian state media blamed the explosion on "terrorists," the BBC reported.
As the fighting continues around Damascus, a top United Nations official called Saturday for the government of President Bashar Assad to declare a cease-fire so residents trapped in the capital's suburbs can be evacuated. Valerie Amos, the under secretary for humanitarian affairs, said about 3,000 people in Moadamiyeh are living in appalling conditions.
The Syrian Observatory for Human Rights said the al-Qaida-linked Nusra Front was responsible for the car bombing in the mainly Christian area of Jaramana on the outskirts of the capital. The blast set off fighting at a major checkpoint in Jaramana and in the rebel-held city of Mleha.
Rebels fired rockets into Jaramana, which is still held by the government, and Syrian fighter jets responded by striking parts of the city held by opposition forces, SOHR said.
Syria's state-run news agency SANA confirmed a suicide attack occurred near the country's capital but made no mention of casualties, CNN reported.
The United Nations says more than 100,000 people have died since the conflict began in March 2011.
About half of those living in Moadamiyeh were evacuated last Sunday but continued fighting has halted the rescue effort.
"I call on all parties to agree an immediate pause in hostilities in Moadamiyeh to allow humanitarian agencies unhindered access to evacuate the remaining civilians and deliver life-saving treatment and supplies in areas where fighting and shelling is ongoing," Amos said
The U.S. State Department on Friday condemned the "continued siege" in the Damascus suburbs and said children are dying of malnutrition a few miles from Assad's palace.
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