Washington (CNN) -- Hoping to quell growing concerns in Congress about enhanced security procedures for airline passengers, top administration officials who oversee airport security went to Capitol Hill on Tuesday to explain the new methods and why they are needed.
The closed, nearly two-hour briefing for congressional staff members included a detailed explanation of new advanced imaging technology that has sparked outrage from some passengers because it captures an image of their bodies through their clothing. Also, Transportation Security Administration officials demonstrated the invasive pat downs required for passengers who either refuse a full body scan or who need a follow-up inspection after an image is taken.
"I feel bad for the girl they put in front of 50 people when they were doing a pat down," said one Republican senate staff member about the female TSA employee who was part of the demonstration, reflecting the concerns of many passengers about being touched in their private areas by security agents.
However, a Democratic staffer who was there said it was all very professional.
"I don't think there was an emotional reaction one way or another," the aide said. "They explained -- based on what we know and what the threat is -- we think this is the best way to mitigate the risks."
Another aide, who refused to say if he was a Democrat or a Republican, said the briefing would help lawmakers "understand the difference between a standard pat down and a more rigorous one."
A Department of Homeland Security undersecretary and two TSA assistant administrators conducted the briefing, the second of two such meetings on Capitol Hill this week.
The security agency set up the briefings after being "deluged" by calls for more information from congressional offices, which were themselves getting questions from angry and confused constituents, according to an administration official who asked not to be identified because he wasn't authorized to speak about the closed briefing.
"Folks are getting a lot of concern from the constituents and they just want to be able to answer phone calls that they get at their offices," said the official, who described the session as "a very grown-up exchange of questions and answers."
One Democratic aide said the TSA's effort to boost security has become a public relations problem because images of the tough new procedures are disturbing to many people.
"It's always tough for the government to get their side of the story out compared to how quickly someone with YouTube video, Facebook, Twitter, all those things, can. For all the things they are trying to do to get the word out, one single isolated incident gets a lot more press than all the efforts they're trying to do," the aide said.
Two GOP aides who spoke to CNN complained that despite the briefing being labeled by Transportation Security Administration as "SSI" -- containing "security sensitive information" -- staffers were not required to show identification when they arrived. They simply signed an attendance sheet that was passed around.
"They have no clue who was in there," one of the Republican aides said.