or updates during the holidays, go to the Transportation Security Administration's Web site at http://www.tsa.gov/public/index.jsp; or to the Department of Homeland Security's site at http://www.dhs.gov/dhspublic.
Department of Homeland Security Secretary Tom Ridge said the nation would remain at the "Code Orange" high alert through the New Year's holiday and perhaps beyond.
"We are as concerned today as we were yesterday," Ridge said. "We'll be concerned as much this week as we were last week."
The administration raised the terrorism alert level to orange, or high, Dec. 21, citing nonspecific but credible threats of an imminent terrorist attack.
Meanwhile, truck inspections will continue at a heightened pace. And when intelligence information indicates it is necessary, international flights that enter U.S. airspace will be required to carry an armed law-enforcement officer aboard.
There has been no indication so far that any country will refuse U.S. demands to place guards on designated flights.
For months, U.S. security officials have feared that al-Qaida operatives would again hijack planes to use them as missiles. The most recent concerns centered not on domestic passenger flights, but on airliners or cargo planes that take off from overseas and cross over U.S. airspace, either on their way to a U.S. airport or to a foreign one,The Associated Press reported.
Emphasis on planes and trucks
Trucks - especially tankers and hazmat rigs - are receiving more vigilant scrutiny at the border after Homeland Security Secretary Tom Ridge raised the national terror alert to orange.
The action comes on the heels of a recent warning by the Department of Homeland Security that Lake Erie-area trucking companies should watch out for what the agency said was possible terrorist activity involving trucks in the region.
Meanwhile, truck checkpoints throughout several states were heightened at bridges and highways, and many weigh stations across the nation remained open for 24-hour mandatory truck inspections.
For example, Ohio Gov. Bob Taft has called on the Ohio Highway Patrol to open truck weigh stations for 24-hour inspections in Dayton, Columbus, Cincinnati, Akron, Cleveland and Youngstown - and all trucks must stop.
In California, on the southbound approach to the Golden Gate Bridge and on northbound Highway 101 near Candlestick Park, the California Highway Patrol set up mandatory truck stops and checked the drivers and the manifests of trucks going in and out of the Port of Oakland. CHP teams focused on hazardous materials loads.
Inspections have increased at all 301 entry points along the nation's borders, and holiday leaves for Customs and Border Patrol agents were canceled, said Robert Bonner, commissioner of the Bureau of Customs and Border Protection.
"We are increasing our scrutiny of both people and vehicles coming into the United States," Bonner told The Associated Press. A particular focus, he said, is the screening of cargo containers at seaports.
Across the country, security is heightened for key bridges, tunnels, seaports and landmarks, such as the Gateway Arch in St. Louis, as well as at nuclear and chemical facilities and other installations that might be vulnerable to attack.
--by Dick Larsen, senior editor