John Brennan, assistant to the president for counter-terrorism and homeland security, coordinated a conference call with Homeland Security Secretary Janet Napolitano, Director of National Intelligence James Clapper, FBI Director Robert Mueller, Director Michael Leiter of the National Counter-Terrorism Center, Deputy CIA Director Michael Morrell, members of the president's traveling staff and others to review the additional steps being taken to ensure vigilance throughout the holiday season.
Earlier this week, Brennan told reporters the United States is working closely with other governments to prevent any terrorist attacks and noted cooperation between U.S. agencies has been strengthened.
"Protecting the American people from the scourge of terrorism is an ongoing and constantly evolving process," Brennan said. "It is the goal of the counter-terrorism community to stay several steps ahead of our terrorist adversaries so that we can stop terrorists dead in their tracks before they are able to carry out either small-scale or potentially devastating attacks."
Last Christmas Day, Umar Farouk Abdulmutallab, 24, of Nigeria, allegedly attempted to blow up a Northwest flight to Detroit from Amsterdam with materials hidden in his underwear.
Officials said Abdulmutallab, a college student and son of a wealthy Nigerian banker, told them he had obtained the explosive chemicals and a syringe that were sewn into his underwear from a bomb expert in Yemen associated with al-Qaida.
"We will not rest because we know that al-Qaida and other organizations are still out there," Brennan said. "We're going to do our best to disrupt these plots and their plans before they ever make it to the homeland."
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