Saudi Arabia yesterday vowed not to rest until the capture of suspected al-Qaeda militants who blew up a housing compound killing at least 17 people and wounding about 120 more, as the US warned of more al-Qaeda attacks to topple the Saudi government and royal family.

"It is quite clear to me that al-Qaeda wants to take down the royal family and the government of Saudi Arabia," US Deputy Secretary of State Richard Armitage told Al Arabiya television, excerpts of which were broadcast yesterday.

The world's biggest oil exporter, battling a surge in Islamist violence, said it would hunt down those behind the attack on a housing compound in Riyadh and, along with Washington, blamed al-Qaeda.

"We will get the perpetrators... who claim to be Muslim," Interior Minister Prince Nayef bin Abdul Aziz said, insisting the kingdom would not be destabilised as US President George W. Bush offered full support.

"We will get to them, God willing, no matter how long it takes," Nayef pledged after inspecting the devastated al-Muhaya residential compound west of Riyadh.

"This will be the job of all the sons of this homeland, chiefly security forces, until we can rest assured that our country is free of devils and wicked people," he said.

The former Saudi intelligence chief, describing the compound of mostly Arab expatriate workers as a soft target, said the kingdom had had successes against militants in the last six months. "There have been many arrests, many discoveries of arms caches, munitions and explosives," he said.

The suspected al-Qaeda bombers posing as police blew up their explosives-rigged car in the Muhaya compound in the Saudi capital.

MILITANTS THREATEN SAUDI STABILITY

Saudi media said the Riyadh blast had taken the battle to an unprecedented level, threatening the stability and economy of the country.

Local newspapers, which usually reflect government thinking, said the suicide attacks which killed mostly Arabs had robbed militants of their claim of fighting the "infidel" presence in the cradle of Islam.

Armitage, who arrived in Riyadh on Sunday, told reporters: "I can't say that last night's attack was the only or the last attack. My view is these al-Qaeda terrorists -- and I believe it was al-Qaeda -- would prefer to have many such events."

The blast ripped an avenue of destruction through the 200 villas in the compound, just days after Western nations issued fresh terror alerts and Washington shut its missions in the kingdom, the world's biggest oil exporter.

The Saudi ministry official said seven Lebanese, four Egyptians, one Saudi, one Sudanese and four unidentified people had been killed. The dead included five children.

Four Americans of Arab origin and six Canadians were among the injured, whose countries of origin also included African and Asian states.

There were no details of the attackers, except that Saudi sources said there had been at least two.

Western embassies in Saudi urged their nationals to remain vigilant and restrict their movements.

Interior Minister Prince Nayef said the kingdom would not be shaken by the attack and vowed, "We will get the perpetrators, no matter how long it takes."

In May a triple suicide bombing at Riyadh housing compounds killed 35, including nine Americans, and was blamed on al-Qaeda.

In October, Saudi officials said the kingdom had arrested nearly 600 people since those bombings, around 190 of whom have since been released. Police and militants have been clashing on a steady basis since May, and there have been frequent seizures of large caches of weapons and explosives.

Magnus Ranstorp, terrorism expert at Britain's St Andrews University, said Sunday's attack was clearly al-Qaeda-inspired and part of a long-term campaign to bring down what militants regard as a corrupt, Western-backed regime.

"This is nothing to do with the war against the West...(It's about) trying to mobilise strength against the Saudi regime," he said.

But Prince Turki said the attack was "not the sign of anybody who is going to do more, or of someone who is going to succeed in upsetting the social balance or the political structure of the country."