As the last traces of the World Trade Centre fall to earth, the toll of those missing rises to 5,422

Rescue Efforts

As a bereft New York City marked the one-week anniversary of the attack on the World Trade Centre with bowed heads and prayers yesterday, Mayor Rudolph Giuliani conceded for the first time that the chances of finding any more survivors still alive in the disaster zone were "very, very small".

At 8.48 am, when the first airliner came out of the blue sky and rammed into the World Trade Centre's north tower last Tuesday, thousands of residents stopped what they were doing – in many cases making their way to work – and bowed their heads for one minute of respect and mourning.

Overnight, the authorities had significantly increased the numbers of people missing, feared dead, at the World Trade Centre. As of yesterday the total stood at 5,422, up from 4,957. Hundreds more were killed in the crashes of two other hijacked planes at the Pentagon and in Pennsylvania.

For now, the effort in downtown Manhattan remains one of rescue. Only five people have been pulled alive from the wreckage, however, and none since last Wednesday. "We have to prepare people for the overwhelming reality that the chance of recovering anybody alive is very, very small," the Mayor said at a news conference. "Those chances are not totally ended or over. We will still conduct ourselves as a rescue effort and a recovery effort."

So far, just 218 people are confirmed to have died in the World Trade attack, of whom 152 have been identified. They include 37 policemen and 32 firefighters.

Mr Giuliani said he planned to spend his minute's silence with members of his staff at City Hall. "I'll be thinking about how ... the world and the city has just been entirely different," he said. "It was the worst week in the history of the city and it was the finest week in the history of the city," he added, referring to the way city residents have resolved to recover.

The minute's silence was similarly observed all across the country. In New York, radio and television stations stopped regular programming to play the national anthem, the sound of tolling bells or sombre music.

New York Stock Exchange brokers and traders paused in their work and people stopped in the streets of the country's biggest city.

In Washington, President George Bush joined 300 White House employees on the South Lawn to observe the moment of silence exactly one week after the attack.

"Out of our tears and sadness, we saw the best of America," he told a Rose Garden ceremony honouring rescue workers. "We saw a great country rise up to help."

Almost the only place where activity did not halt at 8.48am was the site of the tragedy itself. An army of workers, mostly volunteers, continued to swarm over the wreckage – nicknamed "the pile" by some – struggling to remove some of the largest steel beams, shift the mounds of ash and dust and, where possible, penetrate deep inside in search of anyone living.

The operation will be able to change gear once the New York authorities officially declare that all hope of finding survivors beneath the wreckage has been abandoned.

Whereas for now some of the work is still being approached gingerly in case survivors are found, construction teams would be able to work much more aggressively to shift debris. The crews of sniffer dogs – known in the US as cadaver dogs – would also be removed from the site, giving more space to the large machines.