Cars fill the highway, Nov. 22, in San Diego. November 24 marks the Thanksgiving holiday, one of the busiest travel days of the year. Gregory Bull/AP
Travelers check in for their flights at the United Airlines ticket counter at John Wayne Airport on Nov. 22, in Orange County, Calif. Mark Rightmire/The Orange County Register/AP
Travelers arrive as they greet their family at O'Hare International Airport in Chicago on Nov. 23. Nam Y. Huh/AP
Gov. Nathan Deal and wife Sandra greet US Marines, from left, Staff Sgt. Shawn Kallmeyer, Lance Cpl. Drew Greene, and Lance Cpl. Danielle Harrington, as banners reading 'Welcome Our Troops Home' are unveiled at Hartsfield-Jackson International Airport on Nov. 22 in Atlanta. David Goldman/AP
Ana Casares, of Miami, reads a magazine as she waits to check in her luggage at Miami International Airport in Miami, on Nov. 22. Casares is traveling with her family to visit her relatives in Quito, Ecuador, her family decided to travel early in the week to avoid the Thanksgiving travel crowds. Alan Diaz/AP
A train arrives as passengers wait to board at Amtrak's 30th Street Station on Nov. 23 in Philadelphia. Alex Brandon/AP
People line up to board the train to New York at Amtrak's 30th Street Station in front of artist Karl Bitter's Spirit of Transportation, created in 1895, on Nov. 23 in Philadelphia. Alex Brandon/AP
Travelers check their tickets with security at O'Hare International Airport in Chicago on Nov. 23. Nam Y. Huh/AP
Airline passengers go through security at George Bush Intercontinental Airport on Nov. 23, in Houston. David J. Phillip/AP
The Norton family gives Private Josh Norton a group hug after his return from a nine-month deployment in Iraq, for the Thanksgiving holiday, at Hartsfield-Jackson Atlanta International Airport in Atlanta, Georgia, Nov. 23. Tami Chappell/Reuters
Egypt's President Abdel-Fattah el-Sissi called it a 'terrorist attack' on soldiers defending the country's borders that will 'not go unanswered.'
BySarah El Deeb, Associated Press
Al Youm Al Saabi Newspaper/Reuters
Gunmen armed with rocket-propelled grenades attacked a border guard post Saturday in Egypt's western desert in a brazen assault that killed 21 troops deployed in the province along the border with neighboring Libya.