A MAN holding fake pilot's identification was among eight people detained as police hunting those behind the American terror outrage swooped at airports in New York.

The men "met the profile" of those suspected of being involved in the attacks which are now feared to have killed at least 5,000 people, according to the Justice Department.

But it was unconfirmed whether those detained at JFK and La Guardia were trying to board a flight.

As Europe prepared to mourn the dead with a three-minute silence, a senior Pentagon official said the US was gearing up for sustained military strikes and George Bush was set to visit the remains of the World Trade Centre.

In London, the Queen and Duke of Edinburgh were joining the Prime Minister for a service of remembrance at St Paul's Cathedral.

Smaller services took place across Worcestershire. Worcester city centre fell silent as hundreds of shoppers and workers observed the tribute.

Meanwhile, investigators in the US continued to try to identify terrorist collaborators who may still be in a position to strike.

Data from black box flight recorders recovered from two hijacked planes - one the United Airlines Boeing 757 jet which came down in eastern Pennsylvania, the other the American Airlines 757 which hit the Pentagon - "suggests we haven't seen the end of this current threat", one US official said.

Security services were concerned that terrorists might strike in a different manner, now that airport security had been tightened.

In Washington, the most explicit description yet of American intentions was revealed by Deputy Defence Secretary Paul Wolfowitz, who said the retaliation would continue until the roots of terrorism were destroyed.

"It's not just simply a matter of capturing people and holding them accountable, but removing the sanctuaries, removing the support systems, ending states who sponsor terrorism," he said.

President Bush's visit to New York was due after a day of shattered hope in the smouldering ruins of the two collapsed towers.

The belief five firefighters had survived in the rubble since Tuesday turned out to be a misunderstanding.

Three days into the rescue effort, just a handful of survivors had been found and fewer than 100 bodies recovered, of which only 30 had been identified.

A 10-page form has been issued, asking friends and relatives for every detail, from height and weight to a full medical history and DNA samples from toothbrushes and combs, to maximise the chances of identifying bodies which are found.