In Phoenix's Sky Harbor airport Monday night, Transportation Security Administration agents were on hand to screen employees.
That was quite a change from what investigative reporter Lisa Fletcher from Phoenix affiliate KNXV discovered — a 4½-hour nighttime window during which virtually anything could be brought into the secure side of Sky Harbor, the ninth-busiest airport in the nation.
During those late-night hours, the X-ray machines were turned off and the metal detectors were closed, which means bags with unknown contents could be carried to the airplane-accessible side of the airport.
A longtime Sky Harbor employee, who asked to remain anonymous, told Fletcher that late at night, the airport's security procedures changed. TSA agents left, and airport security guards took over. Only an employee badge was necessary for an all-access pass for four hours, every night.
"I'm telling you, Sky Harbor's not safe and hasn't been for a long time," the employee said. "It's a frightening situation. I've just simply never seen anything like it. I really, honestly have not."
The TSA initially told ABC News that Sky Harbor's security plan is in accordance with its policies, saying the "airport is operating under an approved security program" and the employees' equipment and belongings are subject to random TSA screenings at all times.
But in a reversal Monday afternoon, TSA administrator Kip Hawley told ABC News that after reviewing the situation, the agency decided the airport violated TSA policy, which requires all workers who have access to secure areas be screened.
The TSA has placed Sky Harbor's federal security director on administrative leave, and starting Monday night the airport began screening 24 hours a day.
"For the people who work in the concourse area, they do need to be screened, and that's not clear that was the case in Phoenix, so we are going to make it very clear by having the TSA do the screening," Hawley said.
KNXV-TV's hidden cameras captured what security experts said is a disaster waiting to happen. The cameras caught dozens clearing a checkpoint with bags unchecked.
"It is not security. It truly is not security," said Larry Wansley, the former head of security for American Airlines who now works as a security consultant for the government. "Anything can be going through there."
Wansley watched KNXV-TV's footage showing men with huge backpacks flash their ID card and walk through security without ever opening their bags. He saw one man with a bike show his ID and ride away with a crate on his back, unchecked.
"Clearly this is a very, very imminently dangerous situation," he said. "You've got the front door — TSA has locked it up for the better part of the day, the majority of the day — and then you throw open the back door to be exploited by those that would simply destroy us. And I simply do not understand it, and I'm appalled. I'm shocked and I'm amazed."
Documents obtained by KNXV-TV prove that Sky Harbor has known about the lax security situation for two years. In 2005, airport officials hired an outside company to handle security after passenger flights finished for the day. According to the documents, the airport made the decision that no people or personal items would be searched by those guards.