Three people were killed by mortar fire in a central district of the Syrian capital Damascus on Saturday, a monitoring group and state media said.
Rebels fighting to overthrow President Bashar al-Assad have managed to hit central Damascus with rockets and mortar fire during the three-year-old conflict despite firm government control over the heart of the city.
Residents say the mainly Sunni Muslim insurgents have stepped up the attacks in recent weeks as government forces have tightened their grip over central parts of the country.
At least 14 people were killed by a mortar attack on a mainly Shi'ite area of the capital on Tuesday, one day after Assad - whose Alawite sect is an offshoot of Shi'ite Islam - declared he would seek re-election in a vote in June likely to cement his rule.
Syria's state news agency SANA blamed "terrorists" for Saturday's mortar fire, saying it killed three people and wounded three others when it struck a minibus in the al-Dwel'a area of the capital.
The Britain-based Syrian Observatory for Human Rights
, an anti-Assad group which monitors the violence in Syria, also reported the incident and said three people were killed.
More than 150,000 people have died in Syria's conflict. Millions more have fled their homes and the government has lost control over large swathes of territory, especially in the north and east.
Syrian authorities and rebels in the Old City district of Homs agreed a ceasefire on Friday to allow besieged insurgents to pull out of their last stronghold in the central city.