Christmas decorations are seen in the Cross Hall and Blue Room of the White House on December 2 in Washington, D.C. Brian Cassella/Chicago Tribune/MCT/Newscom
First Lady Michelle Obama reads 'The Night Before Christmas' at the National Christmas Tree Lighting ceremony on the Ellipse near the White House in Washington on December 3. Dennis Brack/Pool/UPI/Newscom
The National Christmas Tree is seen being lit by President Barack Obama on the Ellipse on December 3.
The Reception Room is decorated for Christmas during a preview of the holiday season decorations at the White House on December 2. Olivier Douliery/Abaca Press/MCT/Newscom
President George W. Bush makes his annual Christmas Eve telephone call to U.S. Armed Forces on Dec. 24, from Camp David. Eric Draper/White House/Sipa Press/Newscom
Washington-area children enjoy a brief visit from Chelsea's cat Socks, as the President and Mrs. Clinton hosted a Christmas party in the East Room of the White House, Dec. 20, 1996. UPI/Newscom
President George H.W. Bush reads a Christmas story to his grandchildren, Pierce Bush, Marshall Bush, Barbara Bush, Lauren Bush, Jenna Bush, Ashley Bush and Sam LeBlonde at Camp David in Maryland on Christmas Eve, 1991. White House/CNP/Newscom
President Reagan with First Lady Nancy Reagan and their dog Rex are seen on the South Lawn during a ceremony to light the National Christmas Tree on December 12, 1985. Reagan Library/Three Trees Photos/Newscom
President Jimmy Carter and his daughter Amy celebrate Christmas. Zuma/Newscom
President Gerald Ford waves to the crowd at the lighting of the National Christmas Tree in 1976. Newscom
President John F. Kennedy and First Lady Jacqueline Kennedy stand by the White House Christmas Tree in the Blue Room of the White House on December 13, 1961. Robert Knudsen/JFK Library/UPI/Newscom
A holiday tree ornament featuring former President Theodore Roosevelt hangs on a Fraser Fir in the Blue Room in 2008. Karen Bleier/AFP/Newscom
Days after raising its terror warning to the second-highest level, Australian police detained 15 people, saying a violent attack was being planned. Police declined to provide exact details on the attack.
ByKristen Gelineau, Associated Press
Australian police detained 15 people Thursday in a major counterterrorism operation, saying intelligence indicated a random, violent attack was being planned on Australian soil.