Grenades hit Baath Party building in Damascus

At least two rocket-propelled grenades hit a main ruling Baath Party building in Damascus on Sunday, residents said, in the first insurgent attack reported inside the Syrian capital since an eight-month uprising began against President Bashar al-Assad.

"Security police blocked off the square where the Baath's Damascus branch is located. But I saw smoke rising from the building and fire trucks around it," said one witness, who declined to be named.

"The attack was just before dawn and the building was mostly empty. It seems to have been intended as a message to the regime," he said.

The Syrian Free Army, comprised of army defectors and based in neighbouring Turkey, claimed responsibility for the attack, just as Assad vowed in an interview to crush the insurgency and pursue a crackdown on protests demanding his removal that has killed 3,500 people, by a UN count.

The attack could not be independently confirmed. The authorities have barred most independent journalists from entering the country.

It was the second hit on a high profile target in a week, underlying a growing challenge to Assad, who blames "armed terrorist acts" for the unrest, from a nascent insurgency alongside mostly peaceful protests, which have persisted despite the intensifying crackdown.

"The conflict will continue and the pressure to subjugate Syria will continue," Assad told Britain's Sunday Times newspaper. "Syria will not bow down."

Assad, who inherited power from his father in 2000, is a member of the Alawite minority community, an offshoot of Shi'ite Islam that dominates the state, the army and security apparatus in the majority Sunni Muslim country of 20 million.

"The only way is to search for the armed people, chase the armed gangs, prevent the entry of arms and weapons from neighbouring countries, prevent sabotage and enforce law and order," he said.

In video footage on the newspaper's website, Assad said  there would be elections in February or March when Syrians would vote for a parliament to create a new constitution and that would include provision for a presidential ballot.

The Syrian Free Army said in a statement Sunday's attack came in response to the authorities' refusal to release tens of thousands of political prisoners and pull the military out of restive cities in accordance with a plan agreed between the Arab League and Damascus.

An Arab League deadline for Syria to end its repression of the unrest passed with no sign of violence abating and Assad remained defiant in the face of growing international isolation.

Activists in the central city of Homs said the body of Farzat Jarban, an activist who had been filming and broadcasting pro-democracy demonstrations in the city, was found dumped near a private hospital on Saturday with two bullet wounds.

"Security police are no longer just shooting protesters, they are targeting activists when they least suspect it, such as when they take their children to school. Sometimes they don't shoot to kill but to neutralise," said a doctor from Homs who has fled to Jordan.

"I treated an activist recently...They shot him in the thigh and by the time his family got him to me gangrene had spread and his leg needed to be amputated," he said.

Authorities blame the violence on foreign-backed armed groups which it says have killed some 1,100 soldiers and police.

Tanks and troops deployed in Homs after large anti-Assad protests six months ago. The authorities say they have since arrested tens of "terrorists" in the city who have been killing civilians and planting bombs in public places.

The Syrian Observatory for Human Rights said security forces killed 16 civilians in raids and in shootings on protesters on Saturday, including two at a funeral in Kfar Tkharim in the northwestern Idlib province on the border with Turkey.

The Arab League had set a Saturday deadline for Syria to comply with a peace plan which would entail a military pullout from around restive areas, and threatened sanctions if Assad failed to end the violence.

The League, a group of Arab states, suspended Syria's membership in a surprise move last week.

Non-Arab Turkey, once an ally of Assad's, is also taking an increasingly tough attitude to Damascus.

Turkish newspapers said on Saturday Ankara had contingency plans to create no-flying buffer zones to protect civilians in neighbouring Syria if the bloodshed worsens.

"It's almost certain that Bashar al-Assad's regime is going down, all the assessments are made based on this assumption. Foreign Ministry sources say that the sooner the regime goes down, the better for Turkey," one paper said.

Dissident colonel Riad al-Asaad, organising defectors in Syria from his new base in southern Turkey, said in a television interview with Al Jazeera on Saturday that no foreign military intervention was needed other than providing a no-flying zone and weapons supplies.

He said more deserters would swell his Free Syrian Army's ranks if there were protected zones to which they could flee: "Soldiers and officers in the army are waiting for the right opportunity."

The dissident colonel denied government allegations that neighbouring states were allowing arms smuggling into Syria. He said "not a single bullet" had been smuggled from abroad.

Weapons were brought by defectors, obtained in raids on the regular army or bought from arms dealers inside Syria, he said.

Opposition sources said a Syrian Free Army assault on an Air Force Intelligence Complex in a Damascus suburb two days ago killed or wounded at least 20 security police. Official media did not mention the raid.