UPDATE 1-An explosion heard in the vicinity of Syria's Damascus - State TV

An explosion was heard in the vicinity of Syria's capital Damascus and initial reports point to a "terrorist" attack, Syrian state TV reported on Sunday morning. State TV reported there were injuries but did not give further details. Syria's civil war has killed half a million people, forced more than half the country's pre-war population from their homes and dragged in global and regional powers. Syrian President Bashar al-Assad, whose forces have reclaimed most of Syria with Russian and Iranian support, has clung to power throughout the conflict and is widely seen as being loath to yield power after it ends.