Three Britons were found guilty on Monday of plotting to kill thousands by blowing up transatlantic airliners using liquid explosives, in near-simultaneous attacks aimed to cause massive loss of life.
Ringleader Abdulla Ahmed Ali was found guilty of conspiring to murder thousands in the plot, whose discovery triggered wide-ranging new rules on carrying liquids on commercial aircraft.
Tanvir Hussain, 28, and Assad Sarwar, 29, were found guilty on the same charges of plotting to carry out bombings on aircraft flying from London's Heathrow airport to the United States and Canada.
The three men were previously found guilty of conspiracy to murder, but the jury in their first trial could not decide on charges that they had plotted to kill people by bringing down airliners.
Four other men were found not guilty of the plot and the jury failed to reach a verdict in the case of an eighth suspect, Britain's Press Association reported.
The bombers intended to simultaneously destroy at least seven planes carrying over 200 passengers in August 2006 using explosives hidden in soft drink bottles, prosecutors said.
Home Secretary Alan Johnson hailed the verdicts, saying: "I am pleased that the jury has recognized that there was a plot to bomb transatlantic flights and that three people have been convicted of that plot."
"This case reaffirms that we face a real and serious threat from terrorism. This was a particularly complex and daring plot which would have led to a terrible attack resulting in major loss of life."
The counter-terrorism operation to prevent the plot was the biggest ever in Britain. "I cannot thank enough those involved for their professionalism and dedication in thwarting this attack and saving thousands of lives," he said.
The conspirators were caught before they could put their plan into action following the largest counter-terrorism operation ever carried out by British police.
London police chief Paul Stephenson said at the time the men's intent was to cause "mass murder on an unimaginable scale," while a senior British police source said they could have killed thousands on board and more people if they had detonated the bombs over land.
American officials said the carnage would have been as horrific as the Sept. 11, 2001 attacks on New York and Washington that killed 3,000 people and had huge repercussions for the aviation industry.
This case reaffirms that we face a real and serious threat from terrorism. This was a particularly complex and daring plot which would have led to a terrible attack resulting in major loss of life
Home Secretary Alan Johnson
Hatched in Pakistan
Woolwich Crown Court heard that plans for the attack were drawn up in Pakistan and passed on to Ali. He returned to Britain to assemble a terror cell, gather material and identify targets.
However, he was under surveillance by British security forces at the time.
Undercover officers bugged his flat in east London where he met others to build the bombs, as part of a police investigation that cost a total of $57 million dollars, (40 million euro).
The plan was to smuggle home-made bombs made of hydrogen peroxide onto the planes in soft drink bottles. Refilled batteries would carry the chemical detonator, with the bombs set off using a charge from a light bulb filament.
They would have been assembled and detonated in mid-air by a team of suicide bombers, causing untold damage.
Police believe the design was thought up by a mystery bomb maker with links to the al-Qaeda terror network. He has never been identified.
Ali, who was born in Britain, was inspired by suicide bombers who attacked London's transport system on July 7, 2005, killing 52 people as well as the four bombers, prosecutors said.
Sheik Osama warned you many times to leave our lands or you will be destroyed
Group ringleader Abdulla Ahmed Ali
He is thought to have finalized the plans during a six-month trip to Pakistan in 2005, and intended to teach non-Muslims "a lesson that they will never forget."
Ali threatened further attacks against the West in a suicide video recorded in his flat, warning the British public to expect "floods of martyr operations" that would leave body parts scattered in the streets.
"Sheik Osama (bin Laden) warned you many times to leave our lands or you will be destroyed," Ali said in his video.
"I say to you disbelievers that as you bomb, you will be bombed. As you kill, you will be killed. The time has come for you to be destroyed and you have nothing but to expect ... floods of martyrdom operations."
In their defense, Ali, Sarwar and Hussain had argued that the plot was an elaborate publicity stunt designed to call attention to an Internet documentary attacking British foreign policy.