Syrian government says it has 'restored tranquillity' in Deraa
The US has warned its citizens to leave Syria, after days of unrest in which troops are reported to have fired on anti-government protesters in a number of cities leaving many dead.
On Monday witnesses said the army had advanced into the southern city of Deraa, using tanks to support troops.
The BBC's Owen Bennett-Jones, in neighbouring Lebanon, said communication with Syria was virtually impossible due to a government clampdown, but some footage said to have been filmed in Deraa had got through.
The BBC cannot verify this footage but it is thought to have been shot in Deraa on Monday.