"You would need that many to pull off three different vehicle-borne explosions," said one former CIA official who requested his name not be used.A massive manhunt is now underway across Great Britain for at least three suspects who officials say have been positively linked to the Friday attacks by surveillance photographs and forensic evidence, including fingerprints.
"The Brits simply are not ahead of this cell and they know it," he said.
The two failed car bomb attacks in London Friday appear to be connected to today's attack on the Glasgow Airport terminal, although British officials have yet to declare so officially.
Adding to the intelligence failure, analysts said, is the fact that the driver of one of the failed car bombs had been arrested three years ago and released for lack of evidence.
The two men arrested in the wake of the Glasgow attack today are likely to face intense interrogations from British officials who are desperate to learn the names of other cell members.
"The Brits may talk with a fancy accent, but when it comes to this kind of thing, the gloves will be off," the former CIA official said, citing the techniques used to go after the Irish Republican Army.