A suicide bombing in northern Damascus on Tuesday killed three people and wounded several others, state news agency SANA reported, hours after a girl was killed in a mortar attack in the city.
"A terrorist suicide bomber blew up a van in the east of Rukn al-Din neighbourhood in Damascus," SANA said, citing an official as saying at least three people were killed.
There were no details on how many people had been injured.
A resident of the neighbourhood, reached by telephone, told AFP he had heard an enormous explosion, which shattered the windows of shops and houses near the scene.
Clouds of smoke rose above the site of the blast, which was heard in neighbourhoods several kilometres (a few miles) away.
Pro-regime Al-Ikhbariya television showed images of a huge crater in the ground and a building with shattered windows.
The Syrian Observatory for Human Rights also reported the bombing, saying it had struck near a military supply centre and that preliminary information suggested military personnel were among the casualties.
Earlier on Tuesday, in the central Baramkeh district, "a young girl was killed and several other students were injured when mortars fired by terrorists hit a school compound," SANA said, without giving the victim's age.
"Shells also landed on two (other) schools... injuring four civilians, including a teacher, and damaging the buildings," SANA added.
The Britain-based Observatory confirmed the report, adding that an unknown number of people were injured.
Earlier, state television reported a mortar attack on the same district, near SANA'S headquarters, describing it as "a new attack on Syrian media by terrorists".
The attack left three civilians dead, it added, without specifying whether there were journalists among them.
Elsewhere in Syria, regime troops seized Baba Amr in the central city of Homs, the Observatory said, two weeks after fighting erupted in the flashpoint district.
Rebel fighters had re-entered Baba Amr after the army launched an all-out assault aimed at crushing the insurgency in besieged insurgent enclaves of central Homs.
In recent days, "the army used warplanes, rockets and tank shells to bombard" Baba Amr, the Observatory said, adding that residents who had fled their homes in the district returned to find them "uninhabitable."
In the sensitive Quneitra district, located on Syria's ceasefire line with Israel, rebels seized an air defence base, said the Observatory, which relies on a broad network of activists, doctors and lawyers for its reporting.
The UN says more than 70,000 people have been killed in Syria since anti-regime protests broke out in March 2011, transforming into an insurgency when the regime unleashed a brutal crackdown.
At least 45 people were killed throughout Syria on Tuesday, according to a preliminary toll from the Observatory that was issued before the number of fatalities from the Damascus car bomb was knowN.
On Monday, at least 122 people were killed, the group said.