Patriot Day: Watch Sept. 11 live coverage from across the country

Thousands were killed that day when a series of hijacked planes were flown into the World Trade Center, the Pentagon and an open field in Pennsylvania.

Americans remember 9/11 with tear-choked tributes, pleas to 'never forget'

More than two decades later, Sept. 11 remains a point for reflection on the attack that reconfigured national security policy and spurred a U.S. “war on terror” worldwide.