A total of 17 demonstrators were killed by Syrian security forces across the country on Tuesday, the first day of a three-day Muslim holiday, Alarabiya TV reported.
"Clashes between police and demonstrators began immediately after prayers," rights activists were quoted as saying.
Large demonstrations were reported in cities including Daraa, Idlib, Hama and Homs, and in Damascus suburbs.
The Local Coordination Committee said six protesters were killed in the southern province of Daraa and five near Homs, four were killed in the village of al-Harra and two others in Inkhil.
On Monday, security forces killed at least eight and wounded dozens in raids across the country, according to opposition activists.
More than 2,200 people have been killed in the crackdown on anti-government protests in Syria since the uprising against President Bashar Assad broke out in March.
