People run from the collapse of one of the twin towers of New York's World Trade Center in this Sept. 11, 2001 photo. This image ran on Page 5 of the Butler Eagle.

NEW YORK —- In one of the most audacious attacks ever against the United States, terrorists hijacked two airliners and crashed them into the World Trade Center in a coordinated series of blows today that brought down the twin 110-story towers. A plane also slammed into the Pentagon, bringing the seat of government itself under attack.

Thousands could be dead or injured, a high-ranking city police official said, speaking on condition of anonymity.

“I have a sense it’s a horrendous number of lives lost,” Mayor Rudolph Giuliani said “Right now we have to focus on saving as many lives as possible.”

Authorities had been trying to evacuate those who work in the twin towers, but many were thought to have been trapped. About 50,000 people work at the Trade Center. American Airlines said its two aircraft were carrying a total of 156 people.

“This is perhaps the most audacious terrorist attack that’s ever taken place in the world,” said Chris Yates, an aviation expert at Jane’s Transport in London. “It takes a logistics operation from the terror group involved that is second to none. Only a very small handful of terror groups is on that list. ... I would name at the top of the list Osama bin Laden.”

President Bush ordered a full-scale investigation to “hunt down the folks who committed this act.”

Within the hour, the Pentagon took a direct, devastating hit from an aircraft. The fiery crash collapsed one side of the five-sided structure.

The White House, the Pentagon and the Capitol were evacuated along with other federal buildings in Washington and New York

Authorities in Washington immediately began deploying troops, including an infantry regiment. The Situation Room at the White House was in full operation. And authorities went on alert from coast to coast, halting all air traffic and tightening security at strategic installations.

“This is the second Pearl Harbor. I don’t think that I overstate it,” said Sen. Chuck Hegel, Neb.

American Airlines identified the planes that crashed into the Trade Center as Flight 11, a Los Angeles-bound jet hijacked after takeoff from Boston with 92 people aboard, and Flight 77, which was seized while carrying 64 people from Washington to Los Angeles.

In Pennsylvania, United Airlines Flight 93, a Boeing 757 en route from Newark N.J., to San Francisco, crashed about 80 miles southeast of Pittsburgh with 45 people aboard. The fate of those aboard was no immediately known and it was not clear if the crash was related to the disasters elsewhere. In a statement, United said another of its planes, Flight 175, a Boeing 767 bound from Boston to Los Angeles with 65 people on board, also crashed, but it did not say where.

Evacuations were ordered at the United Nations in New York and at the Sears Tower in Chicago. Los Angeles mobilized its anti-terrorism division, and security was intensified around the naval installations in Hampton Roads, Va. Walt Disney World in Orlando, Fla., was evacuated.

At the World Trade Center, “everyone was screaming, crying, running, cops, people, firefighters, everyone,” said Mike Smith, a fire marshal. “It’s like a war zone.”

“I just saw the building I work in come down,” said businessman Gabriel loan, shaking in shock outside City Hall, a cloud of smoke and ash from the World Trade Center behind him.

Nearby a crowd mobbed a man on a pay phone, screaming at him to get off the phone so that they could call relatives.

Dust and dirt flew everywhere. Ash was 2 to 3 inches deep in places. People wandered dazed and terrified.

This was an excerpt from the front-page story on Sept. 11, 2001.