'High' Terror Alert Ends

Citing a reduced threat of attack, the United States lowered its terror alert from orange, or "high," to yellow or "elevated" on Friday, after weeks of intense security in the nation's airports, cities and skies.

"Based on a careful review of the available intelligence, we have lowered the threat level to yellow," Homeland Security Secretary Tom Ridge told reporters. "We are still concerned about continued threats, but the threat conditions we have been following have diminished."

"I know that we are all thankful nothing happened," he added, thanking the public and law enforcement for their efforts.

Ridge said he could not yet say whether an actual, planned attack was foiled.

Even after the alert status has been lowered, some of the security precautions undertaken during the period when the nation was at orange alert will remain in effect, the official said. The Homeland Security Department was expected to urge airlines and possibly some areas to remain on a higher alert status.

"We have not let our guard down. Yellow still means we are at risk of attack," Ridge said.

Specifically, Ridge said he remained concerned that al Qaeda hoped to use airplanes as weapons.

The level was raised to orange, or the second-highest level, on Dec. 21, with officials saying attacks were possible during the holidays and that threat indicators are "perhaps greater now than at any point" since Sept. 11, 2001.

Officials cited concerns about possible suicide attacks involving aircraft - including commercial passenger aircraft. Ridge cited reports from "credible sources" that Osama bin Laden's terrorist network is trying find holes in U.S. aviation security.

Ridge and others urged Americans not to disrupt travel plans, but over the next three weeks an extraordinary increase in security took place. Ridge called the steps "unprecedented."

Air France canceled six flights between Paris and Los Angeles on Christmas Eve after a request from U.S. officials. This week, French authorities hunted a passenger who failed to show up for one of the flights, but have concluded he was not a threat.

A new directive outlined by the Homeland Security Department required selected international flights that enter U.S. airspace to carry an armed law enforcement officer aboard.

In the days that followed, flights from Britain, France and Mexico were cancelled, boarded, escorted by military jets or told to turn around.

As 2003 ended, revelers from New York to California to Las Vegas saw hovering helicopters and bomb-sniffing dogs with their champagne and confetti as cities hunkered down for the most heavily guarded New Year's Eve in memory.

In New York, workers sealed manhole covers and removed mailboxes to guard against any potential bomb attack in Times Square. Armed helicopters prowled the Las Vegas Strip.

The Washington Post reports the U.S. - concerned that terrorists might attempt to detonate a "dirty bomb" during the holidays - sent nuclear scientists to five major cities to search for the radiological devices.

The newspaper said the casually dressed scientists concealed detection equipment in golf bags and briefcases while they looked for evidence of the bombs in New York, Washington, Baltimore, Los Angeles and Las Vegas.

The threat of terrorism also prompted the temporary closure of the oil tanker terminal in Valdez, Alaska. Tankers load Prudhoe Bay oil destined for other parts of the United States at Valdez, the end of the 800-mile-long pipeline, which carries 17 percent of the nation's domestic oil supply.

Security was strengthened in the Prince William Sound community after U.S. officials said al Qaeda operatives could target remote sites such as oil facilities in Alaska.

Some officials have worried that operatives of the al Qaeda terrorist network were deliberately trying to spoof U.S. and international intelligence networks aimed at uncovering terrorist threats, by planting misinformation on lines of communications they believed were monitored.

However, other U.S. officials said the amount and energy level of the threatening intelligence were too widespread for this to entirely be a disinformation campaign.

Some foreign countries also took exception to the U.S. alert.

Mexican official chafed at orders to ground an AeroMexico flight.

Several countries rejected the call for the armed guards by the United States. Civil aviation authorities in Denmark, Sweden, Finland and Portugal all said they would not allow the sky marshals to travel and would instead cancel flights if there was a strong suspicion of a planned attack.

South African Airways also said it did not believe marshals were warranted and that its present security arrangements, emphasizing prevention on the ground, were adequate.

The British Air Line Pilots' Association said it might advise its members — nearly 90 percent of Britain's 9,200 commercial pilots — not to fly with a sky marshal.

U.S. officials began scanning fingerprints and taking photographs of foreigners arriving at U.S. airports this week as part of a new program to keep out terrorists. In retaliation, Brazil's Foreign Ministry started fingerprinting and photographing arriving Americans last week.