The British-based Syrian Observatory for Human Rights says a third blast has rocked the northwestern Syrian city of Idlib, hours after twin explosions targeting security buildings left at least 20 people dead.
Syria's state-run news agency SANA said the two attacks earlier on April 30 were suicide bombings. The Syrian Observatory for Human Rights said most of the dead were security personnel.
Officials have blamed the attacks on "terrorists" opposed to the government of President Bashar al-Assad.
State-run media also reported that rocket-propelled grenades were fired at the central bank and a police patrol in the capital, Damascus, injuring four police officers.
The violence has continued in Syria despite a cease-fire that was supposed to come into effect two weeks ago under a peace plan brokered by United Nations-Arab League envoy Kofi Annan.
Based on reporting by AFP, dpa, AP, and the BBC