Two explosions rocked Marjeh square in central Damascus on Tuesday, killing at least two people and wounding around 20 others, state television and a watchdog said.
Syrian state television said "terrorist suicide bombers" carried out a twin attack at the square and gave a toll of two dead and 26 injured.
The Syrian Observatory for Human Rights said the blasts were caused by explosive devices planted at the square, which it said killed two people and wounded 20.
Official television channel Al-Ikhbariya was the first to report the blasts and screened images of badly damaged vehicles and bloodied pavements.
"It seems the terrorists have struck again," said a television presenter, using the regime's term to refer to rebels fighting President Bashar al-Assad's troops.
Meanwhile, a grassroots network of activists also reported the explosions but said it was not clear what caused them.
"Two consecutive explosions hit the area near the passports and immigration office in Marjeh," said the Syrian Revolution General Commission.
Areas of central Damascus have suffered frequent bomb attacks through the course of Syria's 26-month war. Most attacks were claimed subsequently by the jihadist Al-Nusra Front.