President Obama, on the second full day of his family vacation in Kailua, yesterday directed that heightened airport security measures remain in place as officials investigate a failed terror attack aboard a Detroit-bound plane.

White House officials began their day at 4 a.m. to prepare with counterparts across the government a briefing for Obama. National Security Council chief of staff Denis McDonough, who is in Hawai'i, homeland security and counterterrorism adviser John Brennan and others in Washington spoke with Obama at 6:20 a.m. by secure telephone conference call at the first family's rented vacation home.

The call lasted less than 15 minutes. Obama left immediately afterward for a trip to the gym.

Other traveling administration aides also were kept in a secure hotel room to receive briefings from investigators, to monitor developments, to feed updates to the president and to coordinate across agencies. Regular updates were sent to the president, who — despite being on holiday — made decisions to continue increased security precautions he put in place after Friday's incident.

On Friday, officials said a man tried to blow up a plane as it prepared to land in Detroit before nearby passengers tackled him.

The suspect, Umar Farouk Abdulmutallab, claimed to have been instructed by al-Qaida to detonate the plane over U.S. soil, said a U.S. law enforcement official. But others cautioned that such claims could not be verified immediately.

Vice President Joe Biden's office also said his national security staff briefed him on the attempted attack on Christmas Day and he has been kept up to date with developments.