Foiled plane bomb plot suggestive of Qaeda-Chertoff

WASHINGTON, Aug 10 (Reuters) The US government raised the security alert on passenger planes and barred air travelers from carrying liquids today after Britain foiled a suspected al Qaeda plot to blow up flights to the United States.

''While this operation was centered in Great Britain, it was sophisticated, it had a lot of members and it was international in scope,'' Homeland Security Secretary Michael Chertoff said. ''This operation is in some respects suggestive of an al Qaeda plot, but because the investigation is still under way, we cannot yet form a definitive conclusion. We're going to wait until all the facts are in.'' The United States is sending air marshals to Britain to provide expanded security coverage to prevent efforts to blow up flights to the United States, Chertoff told a news conference.

FBI Director Robert Mueller told the news conference there was no evidence any of the plotting took place within the United States, which was the center of planning, preparation and execution of the September. 11, 2001, attacks on New York and Washington that killed almost 3,000 people.

President George W Bush had known about the investigation for several days, was briefed about it regularly and knew the arrests were coming, a senior administration official said. He said the decision to move to a red alert was closely coordinated between the two countries.

The Department of Homeland Security said it took the unprecedented step of raising the threat level for commercial flights originating in the United Kingdom to ''severe'' or red, its highest level.

The threat level for all other commercial aircraft operating in or destined for the United States would be raised to ''high,'' or orange, from ''elevated,'' or yellow, Chertoff said in a statement.

Britain said the plot may have involved a ''liquid chemical'' device, and US Homeland Security barred passengers from carrying liquids, including beverages, hair gels and lotions, aboard planes.

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