U.S. officials say it is safe to fly

WASHINGTON — A top White House counterterrorism official tried to reassure the public Friday that it's safe to fly even as she acknowledged that investigators continue to search for some of the terrorists accused of planning to blow up airliners over the Atlantic Ocean.

Frances Fragos Townsend, President Bush's homeland security adviser, did not rule out that some missing plotters may be in the United States.

"There are leads that the FBI is running," Townsend told ABC's "Good Morning America" during a round of morning television interviews.

"We are looking for connections between anyone in the United States and the plotters in the U.K., but we don't have any evidence that there is an active threat or cell here," she told CBS.

Though British officials have arrested two dozen alleged plotters, several suspects remain at large, including the suspected ring leaders of the London plot.

Nonetheless, Townsend said people should continue to fly.

"People ought to feel safe about traveling because of all the precautions we're taking," she said.

More will be learned about the plot in coming days, White House officials say. In the meantime, the U.S. airline system remains on high alert, with tougher passenger inspections expected Friday.

Details continued to emerge about the alleged plot, which officials said they had tracked for months. A congressman briefed by intelligence officials, who did not want to be identified because of the sensitivity of the investigation, said U.S. intelligence had intercepted terrorist chatter and British intelligence helped thwart the plot through undercover work.

British authorities arrested 24 people Thursday based partly on intelligence from Pakistan, where authorities detained up to three others days earlier. More arrests were expected, an official said.

For the U.S. traveling public, already heavy security restrictions got even worse. Thursday night, British Airways banned carry-on bags from all flights between the United States and Britain. On Friday, passengers in the U.S. will be subject to a second security check at airport gates to prevent anyone from carrying onto planes liquids that could be used in an explosion, airline officials said.

Bush said the foiled plot showed the nation was "at war with Islamic fascists who will use any means to destroy those of us who love freedom, to hurt our nation."