LONDON — Authorities in Britain disrupted a “serious” terrorist plan to blow up as many as six airplanes simultaneously in mid-flight on their way from Britain to the United States, FOX News learned Thursday.
Had the plan been carried out, the “loss of life to innocent civilians would have been on unprecedented scale,”? said Britain’s Home Secretary John Reid.
The plot would have seen terrorists smuggling liquid explosives — that could be missed by x-rays during screening — onto planes via carry-on luggage, security sources told Sky News.
British officials quickly banned hand luggage on all trans-Atlantic flights and raised security to the country’s highest level — suggesting a terrorist attack could be imminent.
But a top Scotland Yard official was confident the plot had been foiled, confirming 21 suspects were in custody.
“We think this was an extraordinarily serious plot and we are confident that we’ve prevented an attempt to commit mass murder on an unimaginable scale,” said Scotland Yard Deputy Commissioner Paul Stephenson.
Reid said the police were confident the “main players” were among the 21 arrested.
Officials on the condition of anonymity said there could be up to 50 people involved in the plot.
However, Stephenson, nor Reid, commented on that.
“We have been very successful in arresting those we were targeting but this is a lengthy operation, and no doubt there will be further developments,” Stephenson said.
Those arrested were mainly young, British-born Asian men, Sky News reported.
The terrorists were targeting United, American, Continental airlines, two U.S. counterterrorism officials say. But anonymous sources later told FOX News that British airlines were also being targeted.
A U.S. intelligence official said the plotters had hoped to target flights to major airports in New York, Washington and California, all major summer tourist destinations.
One British police spokesman said the attacks were planned to happen at the same time.
“These were (to be) simultaneous attacks on multiple targets, targeting aircraft bound for the United States,” the spokesman said on condition of anonymity in line with force policy.
The country’s police anti-terrorist chief, Peter Clarke, said the investigation — which reportedly culminated over several months — reached a critical point Wednesday night, and forces realized urgent action needed to be taken.
“We have been looking at meetings, movements, travel, spending and the aspirations of a large group of people,” Clarke said. He said the number, destination and timing of the flights that may have been targeted remained under investigation. “As is so often the case in these investigations, the alleged plot has global dimensions.”
Prime Minister Tony Blair, vacationing in the Caribbean, briefed President Bush on the situation overnight, Blair’s office said. There was no immediate public reaction from the White House. Bush is spending a few days at his ranch near Crawford, Texas.
It is the first time the red alert level in the Homeland Security warning system has been invoked, although there have been brief periods in the past when the orange level was applied. Homeland Security defines the red alert as designating a “severe risk of terrorist attacks.”
“We believe that these arrests (in London) have significantly disrupted the threat, but we cannot be sure that the threat has been entirely eliminated or the plot completely thwarted,” said U.S. Homeland Security Secretary Michael Chertoff.
Chertoff added, however, there was no indication of current plots within the U.S. Numerous flights from U.S. cities to Britain were canceled Thursday morning.
A senior U.S. counterterrorism official said authorities believe dozens of people — possibly as many as 50 — were involved in the plot, which “had a footprint to Al Qaeda back to it.” The official spoke on condition of anonymity because of the sensitivity of the situation.
Another U.S. source in Washington told FOX News that the plot had a “serious Al Qaeda connection.”
The plan involved airline passengers hiding masked explosives in carry-on luggage, the official said. “They were not yet sitting on an airplane,” but were very close to traveling, the official said, calling the plot “the real deal.”
Passengers in Britain faced delays as tighter security was hastily enforced at the country’s airports and additional measures were put in place for all flights. Laptop computers, mobile phones, iPods, and remote controls were among the items banned from being carried on board.
Liquids, such as hair care products, were also barred on flights in both Britain and the U.S., raising the possibility that authorities were searching for a liquid explosive.
Huge lines formed at ticket counters and behind security barriers at Heathrow and other airports in Britain. Ed Lappen, 55, a businessman from Boston, who was traveling with his wife and daughter to Russia, found himself unable to travel further.
“We’re safe, we’re OK,” he said at Heathrow. “Now my daughter is going to get a shopping trip in London.”
Hannah Pillinger, 24, seemed less concerned by the announcement. “Eight hours without an iPod, that’s the most inconvenient thing,” she said, waiting at the Manchester airport.
Most European carriers canceled flights to Heathrow because of the massive delays created after authorities enforced strict new regulations banning most hand baggage.
Heathrow’s block on incoming traffic applied to flights of three hours or less, affecting most of the incoming traffic from Europe, an airport spokesman said on condition of anonymity in line with airport policy.
Officials at Frankfurt’s airport, Europe’s second-busiest, Schiphol in Amsterdam and Charles De Gaulle in Paris said Heathrow-bound planes could instead land at their airports if they needed to.
London’s Heathrow airport was the departure point for a devastating terrorist attack on a Pan Am airplane on Dec. 21, 1988. The blast over Lockerbie, Scotland, killed all 259 people aboard Pan Am Flight 103 and 11 people on the ground.
The explosive was hidden in a portable radio which was hidden in checked baggage.