Three people were killed and 22 others wounded on Thursday in two explosions and a mortar attack against an old district of Syria's capital of Damascus, the state- run SANA news agency reported.

The attacks targeted the al-Kallaseh neighborhood in the old quarter of Damascus, SANA said, spelling no further details.

The incident came as part of daily attacks by the rebels positioned on the outskirts of Damascus.

Separately, SANA said the Syrian troops ambushed a rebel group in the southern province of Daraa, killing 20.

It said some of those ambushed were foreign nationals, including a Saudi citizen.