Syrian security forces have opened fire on anti-government protesters in several regions, killing at least eight people.

Activists say the shootings took place on Friday, with most of the deaths occurring near the capital, Damascus, and in the central city of Homs.

The Syrian government stepped up its crackdown on dissent after thousands of people poured onto streets after midday prayers, with renewed calls for President Bashar al-Assad's resignation.

As the protests got underway, Russian President Dmitry Medvedev said Mr. Assad needed to enact reforms or resign. But he added that Russia opposes foreign attempts to push Mr. Assad from power.

Russia had joined China on Tuesday in vetoing a draft U.N. Security Council resolution that condemned Syria for its crackdown on civilian protesters.

In another development Friday, Syrian Deputy Foreign Minister Faisal Mekdad blamed much of his country's deadly unrest on “terrorists.” He told the U.N. Human Rights Council that criminals had killed more than 1,100 people in Syria.

The world body, which is meeting in Geneva, is reviewing Syria's response to the pro-reform rallies.

The meeting is taking place a day after the U.N. raised its death toll from Syria's seven-month crackdown on dissent more than 2,900.