British police acted urgently overnight, arresting 21 people who were plotting to carry liquid explosives onto as many as 10 jetliners in what U.S. government officials said privately could have been the biggest terrorist attack since 9/11.
Information gathered after recent arrests in Pakistan convinced British investigators they had to act urgently to stop the plot, sources told CNN.
U.S. Homeland Security Secretary Michael Chertoff said the plans were "suggestive of an al Qaeda plot," and President Bush said the arrests are a "stark reminder" that the U.S. is "at war with Islamic fascists."
Bush thanked British Prime Minister Tony Blair for "busting this plot."
Authorities immediately banned all passengers headed to or departing from U.S. airports from carrying any liquid in their carry-ons. The massive lines that resulted at security checkpoints made chaos of air travel worldwide as flights were delayed or canceled.
The effects of the plot rippled across the globe Thursday.