Then they paused for two minutes' silence followed by a rendition of God Bless America.
In a poignant tribute to New York's newest heroes, the traditional bell to signal the opening of trading this morning was rung by representatives of the rescue workers who have been toiling night and day in the search for survivors in the rubble of the World Trade Center.
In early trading, stocks fell to nearly three-year lows in the first 15 minutes.
Wall St watchers feared that shaken consumer confidence could force the US dollar down and trigger a global downturn.
Yesterday, almost $2 billion was wiped from the value of the New Zealand Stock Exchange as markets worldwide braced for the worst.
The Top-40 index fell to its lowest close in nearly three years, finishing down 85 points, or 4.6 per cent.
Markets in Japan, Australia, Hong Kong and Singapore also plunged.
Earlier, CNN reported that two top Pakistani officials had delivered a United States ultimatum to the Taleban: hand over Osama bin Laden or face the consquences.
The two officials delivered the message to Taleban Foreign Minister Wakil Ahmed Mutawakel, saying they had 72 hours to comply.
While these meetings took place, there were growing signs of tension and increased military acitivity along the border between Afghanistan and Pakistan.
The Islamic fundamentalist Taleban warned at the weekend that it would attack Pakistan if it provided help to the United States against Afghanistan.
Pakistan has since closed its border. A Pakistani Army officer said the Taleban rulers have deployed a force of between 20,000 ad 25,000 fighters just across the border from the Khyber Pass into Pakistan.
They had moved up a large arsenal of weapons, including Russian Scud missiles.
At the same time the Taleban announced they had shut down their airspace and placed their air defences on alert.
They warned all international airlines to avoid using their air space and said they would act against anyone ignoring the order.
The United States has deployed up to 50 agents, including some from the special forces, in Pakistan, Western and Pakistani sources told Agence France Presse.
The majority of the agents arrived overnight late last week when Islamabad airport was closed mysteriously for five hours.
US officials, in stronger language than before, pointed the finger at bin Laden and his web of dissident groups as the prime suspects in the devastating attacks on the Pentagon and the World Trade Center.
New Zealand backed US calls for an international effort against terrorism, and Prime Minister Helen Clark hinted that elite SAS troops could be deployed.
The cabinet delegated authority to a committee of five, including Helen Clark and Deputy Prime Minister Jim Anderton, in case a decision on New Zealand's response is needed at short notice.
President George W. Bush said those who attacked the US had "aroused a mighty giant".
"We've never seen this kind of evil before, but the evildoers have never seen the American people in action before either - and they're about to find out."
In the rubble of the World Trade Center, weary rescue workers toiled for a sixth day, as the official number of people declared missing dipped to 4957. At last count, 190 people were confirmed dead, and 115 have been identified.
New York Mayor Rudolph Giuliani cautioned that it was "very possible" some of the missing might never be found.
Law enforcement officials tightened the net on those believed responsible for the meticulously planned attacks, adding at least 50 new names to the people wanted for questioning.
A man was arrested in New York as a material witness, following the arrest of a man at Kennedy Airport who had a fake pilot's licence. A further 25 people are being kept in custody for immigration violations.
Map: Opposing forces in the war against terror
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: 0168 1800 932 8555
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: 0168 1800 245 0999
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: 0800 872 111
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