At Los Angeles International Airport, ATA Flight 214 from Los Angeles to Chicago - with 184 passengers - was delayed by more than six hours when authorities responded to a bomb threat.
Federal Aviation Administration spokesman Jerry Snyder says the threat - phoned in directly to the airline - did not refer to any specific flight.
"Apparently a male caller had called in a rather ambiguous question of whether or not there was a bomb aboard an aircraft," says Snyder.
Honolulu International Airport was evacuated for about two hours, after a security screener reported seeing what she believed was a gun in a bag.
Officials now think that image was a computer-generated false image of a gun, which is routinely projected at random several times during a screener's shift, to test for alertness.
At Denver International Airport, three concourses were evacuated and closed briefly after a screener became concerned that a man accompanying a wheelchair-bound passenger might not have been appropriately screened.
At Salt Lake City International Airport, the trouble was outside. A runway was shut down when a pilot reported seeing a man with a gun walking across a snowy field north of the airport.
Authorities say he turned out to be a hunter who may have been lost and disoriented because of a diabetic attack. He was taken to a hospital.
In Memphis, more is coming out about Friday's scare involving a man charged with trying to board a flight with a loaded 9-millimeter Beretta in his briefcase.
Barry Brunstein, 55, of Tampa, Fla., says he is a transportation safety consultant.
Brunstein explains that he took the weapon with him on a business trip to Orlando this month, checked into a hotel, put the gun in his briefcase and didn't use either again until his Memphis trip.
Brunstein, who worked in the 1970s as a U.S. Department of Transportation safety officer, is worried that the incident will affect his consulting job.
"My business is based on credibility, and this can destroy that," says Brunstein.
He says at the time of the arrest, he was making a round-trip jaunt between Tampa and Memphis, with a stop in Atlanta, to complete requirements for a Delta Air Lines frequent-flier program, he said.
Tampa security guards missed the gun when his briefcase was screened there, federal officials said. The briefcase was not screened in Atlanta because he remained near his gate while waiting for his connecting flight.
But Brunstein was pulled over for a random security check in Memphis and arrested when a security guard found the weapon as he prepared to board a flight to Tampa.
"I never gave it a second thought," Brunstein said. "I got off the plane, stretched my legs, worked on some files. Then they did a random search and here we are."
Brunstein's hearing is scheduled for Jan17 in federal court. He is charged with attempting to board an aircraft while carrying a concealed weapon.
He has no previous criminal record and was released on $5,000 bail.
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