How one tip destroyed huge air-terror plot

It all began with a tip: After the July 7, 2005, subway bombings in London, British authorities received a call from a member of the Muslim community, reporting general suspicions about an acquaintance.

From that vague piece of information, according to a senior European intelligence official, British authorities opened the investigation into what they said turned out to be a well-coordinated, long-planned plot to use liquid explosives to bomb multiple U.S.-bound trans-Atlantic flights, an assault designed to rival the scope and lethality of the Sept. 11 hijackings.

By late 2005, the probe involved several hundred investigators on three continents who kept dozens of suspects under close surveillance, even as some suspects traveled between Britain and Pakistan to raise money, find recruits and refine their scheme, according to interviews with U.S. and European officials.

Investigators eventually pieced together enough information from a blizzard of stakeouts, tips and wiretaps to make clear that something big was in the works, and that the plotters' preparations were nearing an end.

"It's not like three weeks ago all of a sudden MI5 knew about this plot and went to work," a U.S. law-enforcement official said, speaking of the British security service. "They'd had a concern about these guys for some time, for months. Details started to emerge, and it became clear over the last couple weeks the nature of the threat and the individuals."

The official, like others interviewed, spoke on condition of anonymity.

The shape of the operation changed regularly as would-be bombers considered which trans-Atlantic flights to target and prepared for a practice run, which was expected to take place within days, U.S. law-enforcement officials said.

British police conducted numerous searches and raids Wednesday and Thursday, detaining at least 24 people in London, the suburb of High Wycombe and the city of Birmingham. While not identified by name, they were described as British citizens, in their 20s, and perhaps entirely of Pakistani origin. Many had traveled to that country recently, the officials said.

Indeed, two Britons of Pakistani origin were arrested in Pakistan about a week ago and provided investigators information, a Pakistani official told The Associated Press.

Many young Muslims in Britain are angry with the U.S. and British governments over the wars in Iraq and Afghanistan. Three of the four suicide attackers who killed 52 passengers in London's transit system last summer were British citizens of Pakistani origin, investigators concluded. The fourth was identified as a Jamaican-born convert to Islam.

British officials would not say if they recovered physical evidence or bomb-making materials in their raids this week. Neither would they describe what kind of liquid explosives the suspects allegedly were planning to use.

U.S. counterterrorism officials said the explosive was a peroxide-based compound but would not give further details. One reason, they said, is that the chemicals are easily obtainable and difficult for airport-security screeners to detect.

The officials said the plotters intended to strike at United, American and Continental airlines' flights to New York, Washington, D.C., and California. But law-enforcement officials said no specific cities were targeted, just the United States in general. A U.S. intelligence official who would not be quoted by name said British Airways flights also were targeted.

Investigators believe the operation was composed of three distinct cells, whose members may not have been aware of one another or the extent of their assignment, U.S. officials said.

British and U.S. law-enforcement authorities decided against breaking up the cells right away in hopes they could learn more about the origins of the network and assemble evidence. But they decided this week to close down the operation after becoming increasingly worried that there were other bombers they had failed to locate or identify, U.S. officials said.

A senior U.S. law-enforcement official said the theory was that bombs would be detonated in midair, similar to the so-called Bojinka plot, a code name used by Osama bin Laden operatives for a 1995 plan to bomb 11 U.S. airliners simultaneously over the Pacific Ocean.

A law-enforcement bulletin issued Thursday by the Department of Homeland Security and the FBI described the conspiracy as "international in scope" but said there was no evidence the plotters or any accomplices had set foot in the United States.

One U.S. intelligence source, however, said some arrested British suspects had made calls to the United States.

British officials suspect up to 50 participants and accomplices were involved, U.S. law-enforcement officials said. Internet searches by the suspects suggested they had considered targeting up to 10 flights, investigators said, although there was no evidence those arrested had bought tickets or made reservations.

"It's fair to say they were aiming for multiple flights, and some of the exact data of who they would deploy and how many might be in one deployment are somewhat ambiguous," said Michael Jackson, deputy secretary at the Department of Homeland Security.

Counterterrorism officials said the basic outline of the conspiracy was known for several months. Investigators from New York to Islamabad, Pakistan, said they were briefed by their British counterparts late last year.

Pakistani officials said Thursday they were informed about the plot in December and assisted with the investigation.

Although Pakistani officials would not divulge how many people were detained in that country, they said the arrests were carried out simultaneously with police raids in Britain.

One Pakistani intelligence official said the main suspects visited Pakistan last year and drew financial and motivational support from a small militant Islamic group.

"No doubt there was some stimulation from Pakistan, but almost all key players are British citizens with roots in Pakistan," he said.

Washington Post reporters Dan Eggen, Spencer Hsu, Warren Bass, John Ward Anderson and Karen DeYoung, correspondent Kamran Khan and researcher Julie Tate contributed to this report.

Bank of England freezes

assets of 19 tied to plot

LONDON — The Bank of England froze the assets of 19 people today, naming them as people arrested Thursday in connection with a foiled plot to bomb British passenger jets.

More names might be added to the list, said British Treasury spokesman Nic Stevenson.

Scotland Yard had no comment.

Most of those named were London residents.

The bank released the following names: Abdula Ahmed Ali, Cossor Ali, Shazad Khuram Ali, Nabeel Hussain, Tanvir Hussain, Umair Hussain, Umar Islam, Waseem Kayani, Assan Abdullah Khan, Waheed Arafat Khan, Osman Adam Khatib, Abdul Muneem Patel, Tayib Rauf, Muhammed Usman Saddique, Assad Sarwar, Ibrahim Savant, Amin Asmin Tariq, Shamin Mohammed Uddin and Waheed Zaman.

The oldest person on the list, Shamin Mohammed Uddin, is 35. The youngest, Abdul Muneem Patel, is 17.