Syria said on Saturday that armed groups "exploited gatherings" and killed 17 people, after thousands took to the streets the previous day protesting against President Bashar al-Assad, reported DPA.
Activists said that at least 32 people were killed when security forces used live ammunition and tear gas to disperse thousands of anti-government protesters who took to the streets Friday.
The Syrian Observatory for Human Rights say that at least 825 people have been killed so far, since protests erupted mid-March demanding greater freedoms, reform and the ouster of al-Assad.
"Seventeen civilians, policemen and security forces members were killed by gunfire from armed groups that exploited gatherings of citizens in Idlib and Homs," the official news agency SANA reported.
The armed group also vandalized and burned public and private properties as well as a number of police stations across the country. They "exploited the police's commitment to not open fire to preserve lives," an Interior Ministry official told SANA.
Authorities have blamed "terrorists" and infiltrators for the unrest in the country.
Friday's violence come one day after the United States told al-Assad to either begin reforms or step down. In a speech, US President Barack Obama condemned the use of force against protesters in Syria.
"President Assad now has a choice," Obama said. "He can lead that transition or get out of the way."
The Syrian government has slammed Obama's speech, saying it "clearly shows US interference in Syria's internal affairs."
Protesters have been rallying against al-Assad, who took office in 2000, following the death of his father, president Hafiz al-Assad