Updated at 11:46 a.m. EST
The security system designed to safeguard the U.S. from airplane attacks failed when a Nigerian man allegedly attempted to blow up a Detroit-bound flight Christmas day, Homeland Security Secretary Janet Napolitano acknowledged Monday.
"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," Department of Homeland Security Secretary Janet Napolitano told CBS' "The Early Show" Monday.
Napolitano also said Monday in an NBC interview that "our system did not work in this instance."
Her comments come after remarks to CNN Sunday saying "the system worked" - remarks that drew immediate criticism from Republicans.
Airport security "failed in every respect," Rep. Peter King of New York said Sunday on "Face the Nation." "It's not reassuring when the secretary of Homeland Security says the system worked."
The Obama administration into the two areas of aviation security - how travelers are placed on watch lists and passengers screened - as critics continued to question how Umar Farouk Abdulmutallab, who was on a watchlist with a U.S. visa in his pocket and a powerful explosive hidden on his body, was allowed to board a flight from Amsterdam to Detroit.
"Well, that investigation is still ongoing. And part of that is looking at how this individual got on a plane and also the screening technology that didn't pick up the material that he had on the plane," Napolitano said.
The White House press office, traveling with President Barack Obama in Hawaii, said early Monday that the president would make a statement from the Kaneoho Marine Base in the morning. White House spokesman Bill Burton did not elaborate.
Billions of dollars have been spent on aviation security since the Sept. 11, 2001, terrorist attacks, when commercial airliners were hijacked and used as weapons.
Much of that money has gone toward training and equipment that some security experts say could have detected the explosive device the 23-year-old Nigerian man is believed to have hidden on his body on a flight from Amsterdam to Detroit.
"There is new technology that is being installed and deployed in airports. There has been some resistance. And when you talk about the security measure, there are those who from one side say 'Don't deploy the tech[nology] … it invades our privacy. There are others who are criticizing the rules that were used while failing really to acknowledge that these are the rules that have been in place since 2006."
More Coverage from CBSNews.com:
Al Qaeda: We Planned Flight 253 Bombing
Officials: In-Flight Restrictions Eased
Tracing Bomb Suspect's Journey to Detroit
Expert: New Security Steps a Smokescreen
Al Qaeda's Yemen Branch Rising in Stature
Many Questions, Few Answers in Terror Case
U.S. Failed to Catch Suspect's Active Visa
Abdulmutallab Shocks Family, Friends
Would-Be Bomber Used Powerful Explosive
Who Is Umar Farouk Abdulmutallab?
Tightening Security in U.S.
Abdulmutallab is currently in a federal prison in Michigan, transferred there Sunday by federal marshals after being treated in a hospital for burns sustained during the attack, reports CBS News correspondent Jim Axelrod.
A federal judge in Detroit postponed until Jan. 8 a hearing on a request by the government to obtain a DNA sample from Abdulmutallab. No reason was given.
Authorities now digging in to every aspect of his life. Investigators away the world are checking computer files, searching for videos and personal writing, offering insights into Abdulmutallab's mindset, reports CBS News chief investigative correspondent Armen Keteyian.
Law enforcement officials say he tucked below his waist a small bag holding his potentially deadly concoction of liquid and powder explosive material.
The chemical was the , the same explosive used by the so-called shoe bomber Richard Reid back in 2001. The suspect was carrying around 80 grams of the substance, a law enforcement source told CBS News.
Abdulmutallab, the , has allegedly indicated ties to al Qaeda operatives in Yemen - fertile ground for terrorist training and activity. Yemen's role as a terrorist training ground could prove to be a "game changer" in the U.S. war against extremists, according to CBS News national security analyst Juan Zarate.
"I think that could change the contest of how we view the terror threat, how the administration has to deal with the potential safe haven in Yemen and also how we view other safe havens in Somalia and North Africa," Zarate said.
Harold Demuren, the head of the Nigerian Civil Aviation Authority, says Abdulmutallab's ticket came from a KLM office in Accra, Ghana. Demuren said Monday that Abdulmutallab bought the $2,831 round-trip ticket from Lagos, Nigeria, to Detroit via Amsterdam on Dec. 16.
He paid cash for the ticket and boarded the plane with just a single carry-on bag, reports Axelrod.
Demuren declined to comment about Abdulmutallab's travels in the days before he boarded his Dec. 24 flight from Lagos to Detroit via Amsterdam, saying FBI agents and Nigerian officials view the information as "sensitive."
Abdulmutallab had been placed in a U.S. database of people suspected of terrorist ties in November, but there was not enough information about his activity that would place him on a watch list that could have kept him from flying.
Meanwhile, CBS News has learned the State Department system designed to keep track of active U.S. visas to reveal Abdulmutallab had been issued an active visa allowing him multiple entries into the United States, reports Keteyian.
However, British officials placed Abdulmutallab's name after he was refused a student visa in May.
Home Secretary Alan Johnson added that police and security services are looking at whether Abdulmutallab was radicalized in Britain.
Abdulmutallab received a degree in engineering and business finance from University College London last year and later applied to re-enter Britain to study at another institution. Johnson said Monday he was refused entry because officials suspected the school was not genuine and they then put his name on the list.
Johnson says that people on the list can transit through the U.K. but cannot enter the country.
Officials said he came to the attention of U.S. intelligence last month when his father, Alhaji Umar Mutallab, a prominent Nigerian banker, reported to the American Embassy in Nigeria about his son's increasingly extremist religious views.
In a statement released Monday morning, Abdulmutallab's family in Nigeria said that after his "disappearance and stoppage of communications while schooling abroad," his father reached out to Nigerian security agencies two months ago. The statement says the father then approached foreign security agencies for "their assistance to find and return him home."
The family says: "It was while we were waiting for the outcome of their investigation that we arose to the shocking news of that day."
The statement did not offer any specifics on where Abdulmutallab had been.
Gibbs, the White House spokesman, said the government will investigate its systems for placing suspicious travelers on watch lists and for detecting explosives before passengers board flights.
An apparent malfunction in a device designed to detonate the PETN may have been all that saved the 278 passengers and the crew aboard Northwest Flight 253. No undercover air marshal was on board and passengers and crew subdued the suspect when he tried to set off the explosion. He succeeded only in starting a fire on himself.
Security experts said airport "puffer" machines that blow air on a passenger to collect and analyze residues would probably have detected the powder, as would bomb-sniffing dogs or a hands-on search using a swab. Most passengers in airports only go through magnetometers, which detect metal rather than explosives.
Stiffer boarding measures have met passengers at gates since Friday and authorities warned travelers to expect extra delays returning home from holidays.
Adding to the airborne jitters, authorities , also from Nigeria, who locked himself in the bathroom on Sunday's Northwest flight 253 from Amsterdam as it was about to land in Detroit. Investigators concluded he posed no threat. Despite the government's decision after the attempted Friday attack to mobilize more air marshals, none was on the Sunday flight from Amsterdam, according to a government report obtained by The Associated Press.
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