Washington: Powerful explosives layered in to mailed letters may have been targeted to blow up aircraft rather than Jewish synagogues, security officials now believe as they work out means to counter this new al-Qaeda plot.
As security agencies piece together the potency of the mailed explosives, US officials said, they were looking into potential that these could have meant to be exploded onboard the aircraft.
Deputy National Security Adviser John Brennan told CNN that authorities were looking into "potential that these explosives would have been detonated enroute to targeted synagogues in Chicago while onboard the aircraft or on way to the destinations".
He said that the American experts believed that the letter bombs were crafted expertly and could have been designed by top explosives experts working for al-Qaeda in Arabian peninsula.
The American authorities have intensified the manhunt to trace and nab the bomb makers as the Yemeni police released a female computer engineer saying someone had posed as her to book the lethal documents.
Brennan appearing in the `Show of the Union` said that authorities were still looking weather any more explosives packages remained at large.
"It would be very imprudent... to presume that there are no other packages out there," he said.
Brennan was part of a high-level meeting convened at the White House to chalk out the US response to the new threat and to initiate moves to capture the culprits.
CNN quoting British intelligence officers said that the suspicious packages was flown from Yemen to Cologne airport in Germany, where the world`s leading cargo agency UPS has its hub. From there it was transfered to a plane bound for Britain`s East Midlands airport.
An initial search failed to find the letter bombs and it was only after Saudi tip off that the lethal device showed up under intense electronic search.
CNN said that the situation was worse in Dubai as the bomb travelled on two commercial planes before it was unearth.
The TV network said the US intelligence believed the suspected bomb maker to be a 28-year-old Saudi national Ibrahim Hassan al-Asiri thought to be in Yemen. al-Asiri, brother of another al-Qaeda plotter who tried to kill Saudi deputy interior minister as a human time bomb, was also the man who designed the explosives strapped underware of a Nigerian accused who tried to blow up an airliner enroute to Detroit last Christmas.
US intelligence suspects that al-Asiri along with US born Yemini preacher Anwar al-Awlaki are the leaders of the al-Qaeda`s Yemini faction and that the Saudi national built the two devices as well as suicide jacket to kill the Saudi Prince Naif Bin Abdul Aziz.
Quoting Yemini sources CNN said that security agencies were searching for al-Asiri, who is believed to be holed up in the Marib province. The Saudi national has been jailed twice in his own country on terror charges.