U.S. intelligence has picked up terrorists discussing the use of prosthetic or medical devices to conceal explosives, sources tell ABC News.
The revelation about the intelligence, which is not new but relevant to debate over new security measures at airports, comes as the White House today acknowledged that the implementation of the security procedures has not gone perfectly.
Americans by a 2-to-1 margin support the use of naked image full-body x-ray scanners in airport security lines, but fewer than half back aggressive new pat-down procedures, according to a new ABC News/Washington Post poll. Opposition to both rises among those who fly with any frequency.
The Transportation Security Administration has come under fire for new body scanners and what some say are highly invasive pat-downs.
Thomas Sawyer, a bladder cancer survivor, said he was humiliated after a pat-down broke his urostomy bag, leaving the 61-year-old covered in his own urine. Sawyer said he warned the TSA officials twice that the pat-down could break the seal.
Cathy Bossi, a long-time flight attendant and breast cancer survivor, said the TSA made her take off her prosthetic breast.
"She put her full hand on my breast and said, 'What is this?' I said 'It's a prosthesis because I've had a breast cancer,'" Bossi said. "And she said, 'You'll need to show me that.'"
In recent days, several passengers have come forward to tell such shocking stories about their experiences with TSA officers.
An ABC News employee said she was subject to a "demeaning" search at Newark Liberty International Airport Sunday morning.
"The woman who checked me reached her hands inside my underwear and felt her way around," she said. "It was basically worse than going to the gynecologist. It was embarrassing. It was demeaning. It was inappropriate."
The head of the Transportation Security Administration John Pistole today said that at least one airport passenger screening went too far when an officer reached inside a traveler's underwear, and said the agency is open to rethinking current protocols.
That search was against protocols and "never" should have happened, TSA administrator Pistole told "Good Morning America" today.
"There should never be a situation where that happens," Pistole said. "The security officers are there to protect the traveling public. There are specific standard operating protocols, which they are to follow."
Pistole, responding to complaints from passengers, has said the TSA would not change its pat-down procedures but today said the agency was "open" to changing security procedures.
"The bottom line is, we are always adapting and adjusting prior protocols in view of the intelligence and in view of the latest information we have on how the terrorists are trying to kill our people on planes," Pistole said. "If that means we need to adjust the procedures, then of course we're open to that."
Only a small number of travelers have been subject to pat-downs, officials say. The White House says roughly 340,000 people -- or 1 percent of all travelers -- have been subjected to more intense searches since the new TSA procedures began Nov. 1.
Pistole said the key to travel security is finding the proper balance between protecting against very real threats -- such as the failed cargo bomb plot and the current search for two suicide bombers believed to be at large in Germany -- and protecting individual privacy, something that some passengers claim invasive pat-down procedures have taken away.
A video of a father taking his young son's shirt off so he can be searched has gone viral online with nearly half a million views in three days. The TSA today released a statement saying that it was the boy's father who chose to remove his shirt "in an effort to expedite the screening" and pointed out that no complaint was filed.
Passengers aren't the only ones calling for a new look at security procedures.
TSA screeners are also fed up with the blame being leveled at them and agree that a better system is needed, according to travel blogger Steven Frischling, who spoke to 20 officers about the new procedures and pat downs.
"The frontline people have significant problems with it," he said. "They feel they are handing suggestions up the chain and they're simply not being listened to."
The screeners told Frischling about their discomfort at touching people's private parts, and getting verbally abused by some passengers.
"I was asked by some guy if I got excited touching scrotums at the airport, and if it gave me a power thrill. I felt like vomiting when he asked that," said one officer. "This is not a turnon for me to touch him -- it is in fact a huge turnoff. There is a big difference between how I pat passengers down and a molester molesting people."
The TSA has attempted to downplay the actual number of people who get pat downs, although Pistole today admitted that he'd dropped the ball when it came to informing the public on what it should expect.
"I wish I could say somebody else was responsible for that, but that was my decision, and it was a risk-based decision," Pistole said at a breakfast with reporters hosted by the Christian Science Monitor. "My concern was because we piloted the new pat downs anyway in two airports, Las Vegas and Boston, that we not publicize that because it would then provide a roadmap or a blueprint to a putative terrorist, who may say OK, I know there's 453 airports around the country."
There's also concern about possible health risks stemming from the new scanners, a fear that the White House today said is unfounded.
"The truth is, you have greater [radiation] exposure sitting in an airplane than you do going through one of those machines," White House press secretary Robert Gibbs said today.
The new scanners and pat downs were introduced Nov. 1, but their impact will be felt the most this week, the busiest travel period of the year.
'Opting Out' Protest to Cause Travel Gridlock?
Geoff Freeman with the U.S. Travel Association said the new procedures have prompted an important debate about what passengers would do for the sake of national safety.
"For the first time in a post 9/11 environment, travelers are now saying they're willing to discuss risk, they're willing to discuss tradeoffs; that's the discussion we need to have," he said.
A grassroots Internet campaign to encourage travelers to "opt out" of the full-body scans on Wednesday, the busiest travel day of the year, has officials fretting over a possible travel gridlock.
"I think there is potential there. That would be potentially complicated by a group of people protesting," Pistole said. "If there are no protests, then obviously we'll have just the normal crush of holiday travelers."
Though thousands of Facebook users have said they've vowed to opt out, some say the movement may be overstated and overblown.
"The truth is, most travelers just want to get to their destination as fast as possible," said Genevieve Shaw Brown, senior editor at Travelocity.
Across the nation, there are 385 of the new, full-body scanners at airports, but there are a total of 2,100 security lanes.
That means about 80 percent of security lanes won't have the machines in place.
"Most people will go through business as usual. The metal detector that we've all become used to, taking off the shoes, pouring our liquids in to the tiny little containers, business as usual for the vast majority of people," Brown said.
ABC News' Kevin Dolak and Ryan Creed contributed to this report.