"Obviously this individual should not have gotten on the plane carrying that material. And we can explain all of the reasons, but they're not satisfactory," Napolitano said on CBS' "The Early Show" Monday.
She was more blunt in an interview with NBC. "Our system did not work in this instance," she said.
Napolitano drew criticism following her remark on CNN on Sunday from Rep. Peter King, R-N.Y., who called her out on it during an interview later Sunday morning on CBS' "Face the Nation."
"Earlier today, Secretary Napolitano said the system worked. The fact is the system did not work," King said. "We have to find a bipartisan way to fix it. He made it on the plane with explosives and he detonated the explosives." (Read more on King's comments on the attempted attack.>)
As for how airport screening could be changed, the secretary said Monday that while there are some immediate measures being taken, the administration is also undergoing a broader review of screening and watch list procedures.
"That investigation is still ongoing," Napolitano said. "And part of that is looking at how this individual got on the plane; and also the screening technology that didn't pick up the material that he had on the plane. But now we're also in the process … of imposing some emergency rules, immediate rules … at airports while we work this problem."
White House Press Secretary also addressed the review process in an interview on "Face the Nation" on Sunday.
"We're going to go through the capabilities for detecting and we're going to go through the watchlisting procedures again, some of which are older, and evaluate whether or not they are up to date for the types of threats and security concerns that we have," Gibbs added. "I do think though that in many ways this system has worked -- we just have to continue to keep refining it and stay ahead of what terrorists are trying to do." (Read more on the interview with Gibbs>)
Napolitano also addressed privacy issues over more invasive screening techniques in the "Early Show" interview with co-anchor Harry Smith.
"There is new technology that is being installed and deployed in airports. There has been some resistance," she said, "When you talk about the security measures, there are those who from one side say, 'Don't deploy the technology. It invades our privacy.' There are others who are criticizing the rules that were used, while failing, really, to acknowledge that these rules that have been in place since -- since 2006. We're looking at those rules. We're looking at what happened here. We're looking to make sure that this sort of incident cannot recur, even as we change procedures and install new technology moving forward."
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