The witnesses in Daraa say protesters are angry about mass arrests and are calling for officials involved in the violence to be fired. They spoke on condition of anonymity for fear of retribution.
Activists in Damascus in contact with Daraa residents said police fired tear gas and bullets in the air to disperse the protesters. The report could not be immediately confirmed.
Syrian police sealed off Daraa Saturday after security forces killed at least five protesters in the first sign that the Arab world's pro-democracy push is seeping into one of the region's most repressive countries.