Global financial markets, which steadied after plunging in the wake of the attacks, were expected to remain skittish with all eyes on Tuesday's meeting of the US Federal Reserve, where another half-percentage point rate cut was expected in a bid to bolster sagging economic confidence.
Relief trucks carrying medical supplies resumed the trip to the Afghan capital of Kabul, while aid agencies were gearing up to cope with as many as 7.5 million Afghan refugees likely to suffer as their impoverished homeland teeters on the brink of conflict with the world's sole remaining superpower.
Less than three weeks after the air assaults spurred President George W Bush to launch an international "war on terrorism," Ashcroft said US officials believed there was a risk that hidden cells of militants could mount more attacks.
"We think there is a very serious threat of additional problems and, frankly, as the United States responds, that threat may escalate," Ashcroft told CBS.
Those fears have led to efforts to bolster security as officials prepare for threats ranging from bombs to biological or chemical weapon attacks. Ashcroft is pressing for greater police powers to monitor possible foreign agents.
Bin Laden has been identified by Washington as chief suspect behind the Sept 11 attacks, in which two hijacked commercial aircraft destroyed the World Trade Centre in New York and a third damaged the Pentagon near Washington. One more hijacked plane crashed in Pennsylvania.
In New York, the toll at the World Trade Centre was revised downward as officials found more duplicated and misreported names. Altogether, officials say 5219 people are now missing, including 314 confirmed dead.
With the 189 people dead or missing at the Pentagon including 64 on board the hijacked jetliner, and 44 confirmed dead from the Pennsylvania crash, a total of 5874 people were feared killed in the airborne assaults and hijackings.
In Afghanistan, which has served as a base for bin Laden and his al Qaeda organisation for some five years, Taleban officials have reportedly hidden the fugitive leader in a secure location as he pondered a request from the country's Islamic clerics that he leave voluntarily.
"Only security people know about his whereabouts. Osama bin Laden is under our control," Taleban ambassador to Pakistan Mullah Abdul Salam Zaeef told reporters in Islamabad.
US Defence Secretary Donald Rumsfeld said he had no reason to believe the Taleban had bin Laden -- whose shadowy movements have eluded US intelligence for years.
"Of course, it was just a few days ago that they said they didn't know where he was, so I have no reason to believe anything a Taleban representative has said," Rumsfeld told NBC.
The chairman of the US Joint Chiefs of Staff, Army Gen Hugh Shelton, declined to comment today on reports that elite US troops are already operating in Afghanistan, saying simply that planned US retaliation for the Sept 11 strikes "will not be a conventional war".
Despite the security fears, officials said today that Bush was determined to reopen Washington's Reagan National Airport --which lies just minutes from the White House and has been closed since the Sept 11 attacks.
With their rule over Afghanistan more precarious than at any time since they seized Kabul five years ago, the Taleban suffered setbacks on the battlefield with fighters deserting their side for the opposition Northern Alliance.
The Pakistan-based Afghan Islamic Press reported that Taleban soldiers lost a key western district to the Alliance after heavy fighting, with several hundred of their fighters switching to fight for the opposition.
Rumsfeld signalled a growing US willingness to support the Alliance, saying Washington needed to recognise and support efforts from groups opposed to the Taleban.
"There's no question but there's any number of people in Afghanistan -- tribes in the south and the Northern Alliance in the north -- and clearly we need to recognise the value they bring to this anti-terrorist, anti-Taleban effort, and where appropriate, find ways to assist them," he told NBC.
In an apparent hardening in the US position, the White House warned the Taleban today it would work to drive them from power unless they accede to America's demands.
"We do not want any government to harbour terrorists. And the Taleban government has been harbouring terrorists," White House Chief of Staff Andrew Card told Fox News.
"They should be out of power" if they keep to these policies, Card said, adding he hoped a stable government would replace the Islamic rulers in the Central Asian nation.
Momentum appeared to be building for Afghanistan's former King Mohammad Zahir Shah to act as a neutral figure overseeing a transition of power should the Taleban fall.
Zahir Shah, exiled since 1973, received a firm pledge of support from senior US politicians on Sunday as he prepared to rally Afghanistan's splintered tribes and begin forming a new government of national unity.
The Taleban said today six people were arrested for distributing pro-US pamphlets calling for Zahir Shah's return, and Taleban spiritual leader Mullah Mohammad Omar warned the former monarch not to meddle.
"Forget Afghanistan. You won't be able to solve the issue of Afghanistan in your lifetime," Omar said in a speech broadcast on Voice of Shariat radio.
Meanwhile, the trial of eight foreigners accused of trying to convert Afghan Muslims to Christianity got underway in Kabul with Taleban officials promising that the threat of US attack would not influence the outcome.
A British journalist, Yvonne Ridley of the Sunday Express, was being held by Taleban authorities on suspicion of spying after she sneaked into the country disguised as an Afghan woman to report on the plight of refugees. Her editor dismissed the spying allegation as "absurd and without foundation".
Washington, seeking to cast the conflict as a war on terrorism rather than a clash between the Western and Islamic worlds, has signed up more than 100 countries for its new global coalition, Gen Shelton said.
But Saudi Arabia -- a key US ally and the guardian of Islam's holiest shrines -- said it would not allow foreign forces to launch attacks against Muslim Afghanistan from its territory.
"This is out of the question," Interior Minister Prince Nayef told a news conference.
An Iranian navy commander said 41 US and British warships had arrived in the Gulf and the Sea of Oman and were being monitored for any signs of attack on Afghanistan.
Pakistan's military ruler, Gen Pervez Musharraf, declined to say whether US forces would be based on Pakistani soil -- a dicey question for Islamabad, which backs Washington's anti-terror drive despite support for the Taleban among its overwhelmingly Muslim population.
Musharraf, who has sent two missions for talks with the Taleban's Omar, said he believed chances were slim that the Taleban would defuse the crisis by surrendering bin Laden.
"We haven't been able to succeed in moderating their views," Musharraf told CNN.
- REUTERS
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