When Umar Farouk Abdulmutallab's father in Nigeria reported concern over his son's 'radicalization' to the U.S. Embassy there last month, intelligence officials in the United States deemed the information insufficient to pursue. The young man's name was added to the half-million entries in a computer database in McLean, Va., and largely forgotten. The lack of attention was not unusual, according to U.S. intelligence officials, who said that thousands of similar bits of information flow into the National Counterterrorism Center each week from around the world. Only those that indicate a specific threat, or add to an existing body of knowledge about an individual, are passed along for further investigation and possible posting on airline and border watch lists. 'It's got to be something that causes the information to sort of rise out of the noise level, because there is just so much out there,' one intelligence official said. The report entered on Abdulmutallab, 23, after his father's Nov. 19 visit to the embassy was 'very, very thin, with minimal information,' said a second U.S. official familiar with its contents. Abdulmutallab's alleged attempt to blow up a Detroit-bound commercial airliner on Christmas Day has put the information in a new light, however. It has unleashed sharp criticism of the watch-list procedures and the explosive-detection systems that allowed him to board Northwest Airlines Flight 253 with materials for a bomb. Republican leaders placed responsibility for what they called lapses in preparedness squarely on the Obama administration Sunday, and questioned whether the president appreciates terrorist threats. 'I think there's much to investigate here,' said Senate Minority Leader Mitch McConnell, R-Ky., on ABC's 'This Week.' Senate Homeland Security Committee Chairman Joe Lieberman, I-Conn., joined GOP critics in asking how the suspect had been able to retain a U.S. visa -- issued by the U.S. Embassy in London in 2008 -- after his name appeared in the terrorist database. 'What happened after this man's father called our embassy in Nigeria?' Lieberman asked. 'What happened to that information? Was there follow-up to try to determine where this suspect was?' White House officials struggled to explain the complicated system of centralized terrorist data and watch lists, stressing that they were put in place years ago by the Bush administration. Spokesman Robert Gibbs said President Obama has ordered reviews of the watch-list system and the airport explosives screening. 'The president is very confident that this government is taking the steps that are necessary to take -- to take our fight to those that seek to do us harm,' Gibbs said, emphasizing stepped-up military activity against al-Qaida in Pakistan, Afghanistan, Yemen and Somalia. Homeland Security Secretary Janet Napolitano told CNN's 'State of the Union' that Abdulmutallab's assertions of al-Qaida contacts and training in Yemen were being investigated, but that 'right now, we have no indication' his actions were 'part of anything larger.' A Justice Department official said Abdulmutallab was released Sunday from a Michigan hospital where he was treated for burns suffered in the failed bombing, and was in the custody of U.S. marshals at an undisclosed location. A government motion to obtain DNA evidence from him will be heard at a court hearing Monday, which Abdulmutallab will not attend. He is scheduled to appear in federal court in Michigan on Jan. 8. The youngest of 16 children of a prominent Nigerian bank executive, and the son of the second of his father's two wives, Abdulmutallab was raised at the family home in Kaduna, a city in Nigeria's Muslim-dominated north, relatives there said. He graduated with an engineering degree from City University in London. Later, his father sent him to Dubai to study for an advanced business degree. In July, relatives said, his father agreed to his request to study Arabic in Yemen. The family became concerned in August when Abdulmutallab called to say he had dropped the course but would remain in Yemen for an undisclosed purpose. Several days later, they said, he sent a text message saying he was severing all ties with his family. Relatives said that message provoked his father's visits to the U.S. Embassy in Abuja and to the Nigerian intelligence service. U.S. intelligence officials insisted Sunday that the visit did not occur until mid-November. Abdulmutallab's movements after that are unclear, although Nigerian officials said Sunday that he paid cash for a ticket on a Dec. 24 KLM flight from Lagos to Amsterdam, connecting to Northwest 253 to Detroit on Christmas Day. 'The e-ticket was purchased from KLM airport office in Accra (Ghana) on 16th December 2009,' Nigerian Civil Aviation Authority Director Harold Demuren told a news conference in Lagos. 'His passport was scanned, his U.S. visa was scanned, and the APIS (Advanced Passenger Information System) returned with no objection.' Abdulmutallab's name would have bounced back if he appeared on the U.S. 'no-fly' or 'selectee' watch lists. Although the size of the government's overall terrorist database has expanded since such information began to be systematically collected in 2003, the number of people prohibited from boarding a domestic or U.S.-bound aircraft, or subject to special scrutiny and notification of U.S. law enforcement, has shrunk, from an estimated 30,000 in early 2007 to 18,000 today. Widespread complaints in the past tended to focus on lists seen as too long, rather than too short. Many came from members of Congress who objected to constituents and spouses being delayed or prevented from boarding flights because information about them or someone with a similar name had been listed. The White House review will examine protocols for watch-listing individuals, currently based on a 'reasonable suspicion' standard, according to the intelligence official, who requested anonymity in order to discuss the sensitive issue. The existing system was established by the Intelligence Reform Act of 2004. It was designed to close gaps in intelligence-sharing that allowed a number of the Sept. 11, 2001, hijackers to enter the United States, although the CIA had identified them overseas as terrorism suspects. The reforms set up the National Counterterrorism Center, which administers a huge database of terrorism information called the Terrorist Identities Datamart Environment, or TIDE. Each day, thousands of pieces of intelligence information from around the world -- field assessments, captured documents, news from foreign allies and the media, and reports from worried fathers -- pour into the NCTC computers. At 11 each night, selected information from TIDE is downloaded into the Terrorist Screening Database, or TSDB, administered by the FBI. Overnight entries are examined each morning by an interagency team drawn from across the government. Under FBI direction, individuals assessed as significant risks are then 'nominated' to specific watch-lists, each of which has different criteria. In addition to the 'no-fly' and 'selectee' lists, the State Department maintains a list of people who should not be granted visas; other lists single out people who cross land borders and domestic fugitives. In Abdulmutallab's case, a single, non-specific entry in TIDE was not enough to send his information to the TSDB, so he was never considered for a watch list. Among the gaps in the system already being addressed by computer technicians, officials said, is the absence of an 'automatic feedback loop' that would have let TIDE know that the random report from Nigeria referred to a man who already had a valid U.S. entry visa, issued more than a year before. Staff writers Carrie Johnson and Joby Warrick in Washington, Anne E. Kornblut in Kailua, Hawaii, and special correspondent Aminu Abubakar in Kano, Nigeria, contributed to this report. 