Saudi Arabia went on the offensive Tuesday, warning Islamist militants they will be crushed with an "iron fist" after deploying thousands of troops to the holy cities of Mecca and Medina to protect Ramadan pilgrims.
Security forces have arrested several people, a leading newspaper reported after King Fahd warned overnight of "stiff retaliation" to the devastating suicide attack that killed 17 people at a Riyadh housing compound.
"Several suspects have been arrested in the course of the last two days," said Al-Hayat daily, without giving numbers.
"The security authorities are said to have important information on the basis of which they are looking for suspects," said the Saudi-owned paper.
The Saudi monarch vowed at a cabinet meeting: "The retaliation will be stiff".
The kingdom "will act with an iron fist against all those who threaten the security of the country, its citizens and those who live there."
The declaration came after a security source said at least 5,000 soldiers and police had been deployed in Mecca, where as many as 2.5 million Muslims were expected to celebrate the last 10 days of the fasting month of Ramadan.
The decision to deploy extra forces to the holiest city in Islam was reached after security forces smashed a suspected al-Qaeda cell last week and announced it had been preparing an attack on the faithful in Mecca, said the security source who refused to be named.
"In total there will be no fewer than 5,000 soldiers and police reinforcements in the Mecca region," he said. Press reports said the security contingent had been doubled compared to previous years.
Some two million foreign pilgrims and 500,000 Saudis were expected to throng Mecca over the last 10 days of the Muslim fasting month, which is due to conclude around November 24-25.
More reinforcements would also be deployed in Medina, the second holiest site in Islam, the source added.
Deputy Hajj or Pilgrimage Minister Hatem Qadi Tuesday told Al-Hayat there had been no reduction in the numbers of pilgrims flowing into Mecca, which he estimated already at 1.5 million, despite the bloodshed.
Adding to the difficulties, torrential rains have hit Mecca, with Tuesday's newspapers reporting seven dead, one missing and 48 hurt in flood the previous day.
Mecca has already been the scene of deadly clashes between suspected al-Qaeda gunmen and security forces.
The authorities said November 3 they had foiled a plot to attack pilgrims in the holiest city in Islam where two "terrorists" were shot dead.
The alleged plot was said to have been hatched by fighters of the al-Qaeda militant network headed by Saudi-born Osama bin Laden, who planned to kill pilgrims during Ramadan.
In mid-June police carried out a series of raids on suspected militant hideouts in Mecca, killing five men and arresting 12 others, five of whom were wounded.
A large amount of weapons, ammunition and explosives was reported seized on both occasions.
The king also expressed his condolences to the families of the victims, deploring the fact that "a group of criminal terrorists had committed their act during the month of Ramadan, the month of piety and forgiveness."
His threat of retaliation appeared to leave little room for a mediation offer announced Monday by a group of Saudi religious scholars and clerics.
"A group of learned men and Saudi clerics are now trying to set up a mechanism to launch a dialogue between the government and the youths who have carried out acts of violence, in an effort to halt the bloodshed," Sheikh Abdullah Nasser al-Sobeihi, one of the scholars, said on Monday.
"It's a mediation to build a bridge between the two sides - the government and the wanted youths," he said, noting however that the mediators had yet to offer their services to the government.
Suspected militants of al-Qaeda blew up a Riyadh housing compound at midnight Saturday killing 17 people and wounding 122.
Interior Minister Prince Nayef bin Abdul Aziz vowed Monday that the killers would be caught.
He insisted 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 al-Muhaya residential compound west of Riyadh devastated by the blast on Saturday night.
"This will be the job of all the sons of this homeland ... until we can rest assured that our country is free of devils and wicked people," Nayef said.
The three US diplomatic missions in Saudi Arabia were to remain closed until at least the end of this week, the State Department said, citing continued security concerns.
However the department eased restrictions on the movement of diplomats posted at the US embassy in Riyadh immediately after Saturday's bombing.
Saudi Arabia, where the Prophet Mohammed was born and died, has found itself on the front line of the US-led war against terrorism since the September 11, 2001 attack in the United States, in which 15 of 19 suicide attackers were Saudis.
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