With terror attacks planned for as early as this symbolic four-day Easter holiday weekend in England, Muslim fundamentalist bombers who used student visas to enter the country had identified crowded shopping malls and nightclubs as likely targets as they sought to maximize casualties, according to counter-terrorism sources.
Police sources confirmed for ABC News British media accounts that those possible targets included the Birdcage nightclub in downtown Manchester and the Trafford Center shopping complex, which can have as many as 140,000 shoppers on a weekend.
The use of student visas is the latest wrinkle in the continued campaign of Pakistani-linked terrorists to strike in England. That terror campaign in its most lethal attack killed 52 transit riders on July 7, 2005, and injured several hundred more.
The current Easter Bomb Plot case, dubbed Operation Pathway by authorities, was a long-term police operation, according to senior intelligence officials, and the alleged plotters had been under constant surveillance. The disclosure of top secret documents this week forced authorities to rush to arrest them.
The early take down of the operation was triggered when British media circulated photographs of Scotland Yard's top terrorism official, Bob Quick, on his way to a meeting with the Prime Minister Wednesday, exiting his car at 10 Downing St. holding a document marked "secret" with operational details visible to photographers. The document revealed how many terrorist suspects were to be arrested, and in which cities. It revealed that armed police officers would force entry into homes. The operation's secret code headed the document.
Within several hours of the mid-day release of those photographs -- which appeared on the internet before a government order to prevent publication could be issued -- most of the suspects were in police custody and the searches for evidence were underway.
Nonetheless, some informed experts were concerned that the early takedown could result in a spate of not-guilty verdicts on the most serious charges -- as happened in the 2006 Operation Overt case where, as a result of U.S. meddling, according to British officials, the case against plotters who planned to take down multiple airliners with liquid explosives mixed on board was aborted before British police and intelligence officers were satisfied they would have enough evidence to win guilty verdicts.
But other knowledgeable experts in Britain noted that as it appeared in this case that the police were just hours or a few days away from concluding their case, the likelihood of such a strong impact on any eventual court cases is probably minimal.
In the past, "homegrown" terrorists including British nationals and residents of Pakistani descent with strong links to Pakistan have organized a number of attacks, including the July 7, 2005 attack that claimed 52 lives and injured hundreds of others.
Additionally, terror attackers originally from East Africa but with ties to Pakistani terrorist leaders were tied to the aborted July 21, 2005 London transit system attacks.
But with the homegrown plotters under intense pressure from authorities who are using aggressive surveillance on all active cells and who have foiled 16-18 full blown terror plots since 2004, and disrupted at least several dozen more, terrorist plotters exploited a loophole in the student visa process to send foreign operatives into Britain.
By Wednesday evening, political pressure -- apparently orchestrated behind the scenes by members of the country's conservative party -- had escalated to the point where Quick was forced to resign from office.
On Friday, evidence searches continued in areas including Liverpool, where a block of apartment buildings was evacuated as evidence teams collected large amounts of material and bomb squad team members stood by should they have been needed. The possibility that the attackers were linked to a group that planned simultaneous attacks inside of Pakistan have raised concern among U.S. and UK terror officials about a growing aggressive stance.
Of those arrested, 11 males were Pakistani nationals, and 10 were on student visas. One of those arrested was British. The arrest occurred in places including parking lots, residences and a university campus. At least 10 locations were raided by police as they collected their evidence.
It was unknown if explosives or the common household and commercial chemicals used to make them had been seized in the raids. But hazardous material and explosives experts were present throughout the operation.