The fresh surge of violence came as Russian President Dmitry Medvedev said Assad will have to leave power if he fails to implement reforms acceptable to the opposition, and Damascus again blamed "terrorists" for the unrest.

Four civilians, including two elderly men, were shot dead in the central city of Homs by security forces and four others in the outskirts of Damascus, the Syrian Observatory for Human Rights said.

Kurdish activist and opposition spokesman Meshaal Tamo, 53, was killed when four masked gunmen stormed his house in Qamishli in the north and opened fire, also wounding his son and another fellow activist in the Kurdish Future Party, activists said.

Thousands of Kurds took to the streets in Qamishli after Tamo's death, and gathered outside the hospital where his body was taken.

The official SANA news agency reported Tamo's "assassination," but gave a different account of his death. It said he was killed "by gunmen in a black car who fired at his car."

Tamo, a member of the newly formed Syrian National Council (SNC) opposition grouping, had been released recently after three and a half years in prison.

A 10th man was shot dead on Friday by security forces in the flashpoint northern town of Jisr al-Shughur near the Turkish border, the Local Coordination Committees activist network reported.

Meanwhile, prominent opposition figure and former MP Riad Seif had to be given hospital treatment after being beaten outside a mosque in the capital's commercial neighbourhood of Medan.

Mosques in Syria, as happens every week, again became springboards for Friday anti-regime protests, also this time in support of the SNC, formed to represent the main opposition groups, activists said.

Pro-democracy activists had called for fresh demonstrations under the banner: "The Syrian National Council is our representative, mine, yours and that of all Syrians."

Demonstrators in the restive Damascus district of Barzeh carried slogans affirming their "complete support" for the SNC, YouTube videos showed, while protesters in Homs chanted "the people want the fall of the president."

In the Homs neighbourhood of Qurabeyd, demonstrators raised their shoes -- a sign of disrespect -- alongside photographs of Assad with his face crossed out, a YouTube video showed.

Activists also documented anti-regime and pro-SNC rallies in the Damascus neighbourhood of Qabun, the eastern town of Abu Kamal and Qamishli in the north, where security forces fired on protesters and arrested 10.

Security forces and paramilitaries locally known as the "shabiha" surrounded mosques in Damascus suburbs, in Homs and in the Mediterranean cities of Banias and Latakia, activists said.

In Daraa, thousands of demonstrations trampled on giant Russian and Chinese flags, in a sign of discontent at the two UN Security Council members blocking a resolution calling for "targeted measures" against Assad.

The deputy foreign minister of Syria, which has yet to comment on the formation of the SNC, said in Geneva that more than 1,100 people have been killed by "terrorists" in the revolt that has shaken the country since March.

"Syria is grappling with terrorist threats," Faysal Mekdad said in a speech to the 47-state UN Human Rights Council.

"In the next few days we will give the High Commissioner for Human Rights a list of martyrs... civil servants, police... more than 1,100 people who have been killed by the terrorists," he said.

Russia's Medvedev unexpectedly piled pressure on Damascus, just days after Moscow and China vetoed the UN resolution.

"If the Syrian leadership is unable to undertake these reforms, it will have to go. But this is something that has to be decided not by NATO or individual European countries but by the people and leadership of Syria," ITAR-TASS quoted Medvedev as saying.

In wielding its veto on Tuesday, Russia said it feared the resolution could be used for military action against Syria. Russia, China and others still accuse NATO of abusing UN resolutions on Libya to launch air strikes this year.

The United Nations said it now estimated the crackdown had killed more than 2,900 people since mid-March.

Analysts warn that the unrest, which began as peaceful protests, is becoming increasingly armed in response to the regime's relentless gunning down of protesters.

An army officer who has taken refuge in Turkey, Colonel Riad al-Asaad, claims to have established an opposition armed force called the "Syrian Free Army," but its strength and numbers are unknown.

Syrian troops on Thursday pursued armed defectors near the border with Turkey, sparking clashes in which 12 people died, and crossed into Lebanon to kill a Syrian national, activists and an official said.

Four people died in similar clashes earlier in the week between Syrian troops and deserters, activists said.

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