Syrian security forces opened fire and used tear gas against anti-government protesters in the Damascus suburb of Arbeen, on what has been dubbed "Friday of Having God on our Side" activists reported, killing at least ten protesters throughout the country.

Six people were killed in the Damascus suburb of Arbeen on Friday. Rights activists Mustafa Osso and the Local Coordination Committees, a group that tracks protests, reported at least 10 people wounded in Arbeen.

Activists also said three people were wounded in Homs.

Protesters took to the streets in Damascus, the southern province of Daraa and the central city of Homs following Friday prayers, according to the opposition group Federation of Coordination Committees of the Syrian Revolution.

The group added that security forces had encircled mosques in several parts of Syria to prevent worshippers from joining protests.

The protests were in response to activists' calls to denounce a harsh government crackdown on pro-democracy demonstrations.

The online call for the protests was made as overnight demonstrations were held in several parts of Syria despite tight security.

Protesters have intensified their opposition to the government of Syrian President Bashar Assad since the Muslim holy month of Ramadan began on August 1.

At least 100 people were killed on Thursday when security forces fired on protesters in the central Syrian city of Hama, activists said.

More than 1,500 civilians and around 350 security personnel have been killed since protests started in Syria in mid-March, local human rights advocates say.

U.S. Secretary of State Hillary Rodham Clinton on Thursday put the estimated death toll since March at as high as 2,000 protesters, calling the recent shooting to death of a one-year-old as a "very stark example of what is going on."

It is hard to verify these reports, as the Syrian authorities have barred most foreign media and international human rights groups from the country.