Reports from Syria say at least three people have been killed and scores injured in clashes between protesters and security personnel in the city of Deraa.
Video footage posted on various websites shows large crowds said to be in Deraa chanting slogans against corruption.
Reports from the city say the authorities responded with waters cannon and live fire, killing at least three people and wounding many more.
The official news agency in Syria said infiltrators in Deraa had provoked chaos and set cars and shops on fire, thereby obliging the security forces to intervene.
There are also reports of protests elsewhere in the country and security officials broke up a demonstration after Friday prayers in the main mosque in Damascus.