Afghanistan today defiantly rejected new calls to hand over Osama bin Laden while President Bush sought to allay American fears of possible germ warfare attacks by the prime suspect in last month's mass killings on US soil.
"I understand that many Americans are feeling uneasy," Bush said in his weekly radio address after the discovery of four cases of anthrax, a deadly disease that is a potential biological warfare agent.
"But all Americans should be assured: we are taking strong precautions, we are vigilant, we are determined, the country is alert, and the great power of the American nation will be felt."
While none of the cases has been tied to terrorism, Vice President Dick Cheney said there could be links to bin Laden, blamed by Washington for the September 11 suicide attacks on New York and Washington that killed some 5,500 people.
"I think the only responsible thing for us to do is proceed on the basis that it could be linked," Cheney said, adding that Washington had ample evidence that bin Laden's followers were trained in how to spread biological and chemical weapons.
As US fighter jets resumed bombing Afghanistan after a brief respite for Friday's Muslim sabbath, the ruling Islamic purist Taleban who are sheltering bin Laden flatly rejected Bush's offer to halt the strikes if they handed over the Saudi-born militant.
"We once again want to say that their (the US') intention is a war against Muslims and Afghans," Taleban Information Minister Mullah Qudratullah Jamal said of the "second chance" offer Bush made on Thursday if the Taleban "cough up" bin Laden.
"Osama is not the issue and people have realised this by the crimes they are committing," Jamal told Reuters. "Our jihad (holy struggle) ... will continue until the last breath for the defence of our homeland and Islam."
Bombs shook the Taleban stronghold of Kandahar and the capital, Kabul, on Saturday witnesses said. Bush declared the first phase of the US military campaign against bin Laden a success, saying nearly a week of bombing had disrupted his support networks.
"We have disrupted the terrorist network inside Afghanistan," Bush said. "American forces dominate the skies over Afghanistan and we will use that dominance to make sure terrorists can no longer freely use Afghanistan as a base of operations."
The Kabul correspondent of the al-Jazeera Arabic-language satellite television network said air defences in Kabul appeared to be defective.
"The radars seem to have been damaged," he said, explaining that anti-aircraft fire had started before explosions were heard.
"From my house I could see a bomb land on the airport, I saw a fireball, debris flying up into the sky and the initial big fire then dimming," one Kabul witness said.
At least one man was killed and four injured when either a bomb or missile -- probably meant for the already-heavily targeted airport -- struck a poor neighbourhood near the airport on the outskirts of Kabul.
"We came out and saw all houses had collapsed. It was the enemy's plane and the women were crying. We dug out three wounded from here and one dead person," said one resident.
In Washington, Pentagon officials said that a US warplane missed a Taleban military target at Kabul airport and that a 2,000 pound (900 kg) bomb the plane was carrying apparently struck a residential neighbourhood.
At the scene of the hit, one man sat in his wheelchair, weeping next to a pile of rubble where his house once stood. Other residents wandered about in a daze.
"We lost everything, our house and property," one woman said. "We are so afraid of the attacks we have forgotten our own names and can't even understand what we say to each other."
Kabul residents were torn between flight or fight. Many fled rather than risk another night of fear.
Lines of people could be seen at bus stops in the morning, packed up to leave after enduring five nights of air raids. Others piled their belongings onto rickety donkey-drawn carts and headed out of town.
The Taleban estimated that more than 300 people, mostly civilians, had been killed since the raids began last Sunday.
A senior official of the opposition Northern Alliance, which controls only about 10 per cent of the Central Asian country, said the US strikes had robbed Taleban fighters of the ability to launch a counter-offensive.
"In the last one week there have not been any counter-offensives from the Taleban," alliance foreign minister Abdullah Abdullah told a news conference in Jabal-us-Saraj.
"That is significant. They have lost their capacity to launch counter-offensives," he said.
Abdullah said Saturday's US raids in the northeastern Taloqan district were the first strikes on the frontline between the Taleban and the Northern Alliance.
The Northern Alliance, composed of mujahideen groups thrown out of Kabul by the triumphant Taleban in 1996, has been eagerly hoping the US strikes will hit the Taleban front lines and thus give them a possible opportunity to try to advance from positions where they have been stuck for years.
Asked about casualties among foreigners fighting for the Taleban, many of them Arabs, Abdullah said that the bases of "foreign friends of the Taleban" had been hit. "The number of (casualties) should be hundreds not dozens."
Meanwhile US postal services and corporate mailrooms throughout the United States were on alert for letters containing powder, the method apparently used for spreading anthrax.
A 38-year-old woman aide to NBC news anchor Tom Brokaw, who in late September handled a letter addressed to him that contained a white powdery substance, tested positive for rare skin anthrax on Friday but was expected to recover fully.
Skin anthrax is not as deadly as the inhaled version that killed a 63-year-old employee of American Media Inc. in Florida, and was found in two other employees at the same company. NBC said the letter its staffer handled was sent from Florida.
The bacteria which causes anthrax can form spores, which have been known to kill 89 per cent of patients who do not receive treatment.
In Nevada, a branch of software giant Microsoft Corp. received a suspicious letter filled with pornography that passed one test for anthrax but failed another and now awaits a final test on Saturday, company officials said.
A similar letter was sent to New York Times correspondent Judith Miller, co-author of a just-published book about germ warfare, but she turned it over to police before opening it. That powder tested negative for anthrax.
Scores of businesses across the country clamped down on opening suspicious mail and turned their mail rooms into "hot zones" where employees wore gloves and deposited suspect packages into special containers.
Employees at the Los Angeles Times were locked in the newspaper building for 90 minutes on Friday night after white powder was found near a computer keyboard in the book review department.
The United Nations reported receiving letters containing a white powdery substance.
- REUTERS
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