Bush: Terrorism 'will not stand'

Make no mistake, The United States will hunt down and punish those responsible for these cowardly acts

(CNN) -- Declaring that terrorism against the United States "will not stand," President Bush ordered a full-scale government investigation of the plane crashes at New York's World Trade Center.

"Today we've had a national tragedy," Bush said from Sarasota, Florida, where he had been reading to children at Emma E. Booker Elementary School.

He described the incidents as an "apparent terrorist act."

CNN.COM SPECIAL REPORT  CNN NewsPass Video  Agencies reportedly got hijack tips in 1998  MORE STORIES Intelligence intercept led to Buffalo suspects Report cites warnings before 9/11  EXTRA INFORMATION Timeline: Who Knew What and When? Interactive: Terror Investigation Terror Warnings System Most wanted terrorists What looks suspicious? In-Depth: America Remembers In-Depth: Terror on Tape In-Depth: How prepared is your city?  RESOURCES On the Scene: Barbara Starr: Al Qaeda hunt expands? On the Scene: Peter Bergen: Getting al Qaeda to talk

"I have spoken to the vice president, to the governor of New York, to the director of the FBI and have ordered that the full resources of the federal government go to helping the victims and their families, and to conduct a full-scale investigation to hunt down and to find those folks who committed this act," he said.

Bush, who learned of the incident about 9 a.m., was to return immediately to Washington, where he planned to convene a national security meeting.

At the end of his brief statement, Bush asked for a moment of silence, then said: "God bless the victims, their families and America."

Earlier, the president was reading to children in the school when reporters asked him if he was aware of the two crashes and explosions. The president nodded and said he would talk about the situation later.