The District of Columbia government shut down. Many private firms also closed and sent employees streaming home, causing traffic nightmares.

As parking garages closed and cars poured out, one woman grabbed the door of a lone car going in.

"Don't park," she yelled, her face twisted in fear. "They're hitting the Pentagon! They're hitting the Pentagon!"

Naval officer Clyde Ragland, who works near the Pentagon, was stuck in his office because the streets outside were clogged with traffic.

He and his co-workers were watching television reports of the disaster in New York when "we gazed out our own windows and, to our horror and disbelief, saw huge billows of black smoke rising from the northeast, in the direction of D.C. and the river . . . and the Pentagon."

Ragland described billowing black smoke and "what looked like white confetti raining down everywhere." He said it soon became apparent "that the 'confetti' was little bits of airplane, falling down after being flung high into the bright, blue sky."

"Everything is confusion right now, but there was no panic. Just stunned disbelief," Ragland said.

Streets surrounding the Capitol Mall were paralyzed as people tried to get away from the federal buildings, worried that they would be targeted next.

Federal workers raced down the steps into the subway, only to be greeted by a sign flashing: "Security alert! The Metro is closed until further notice. Please try to call a relative or a taxi if you need a ride." The subway reopened by midday.

But with phone lines jammed and no taxis to be found, many people tried to hurry away on foot, exchanging rumors about the attacks.

"We never thought this could happen," said Mary Shea, 58, an FAA program analyst, as she stood outside the L'Enfant Plaza subway stop. "What a shock, what a shock."

Long lines formed around pay phones.

"My mom works at the Pentagon, my mom works at the Pentagon," one man repeated over and over again, rocking back and forth, urging the line to speed up.

Abigail Harrington, an employee at the District of Columbia Department of Health, stood with a large group of people on 7th Street, peering down the road for a bus she hoped to catch to pick up her daughter from school.

"I feel horrible," said Harrington, clutching her hands together. "I can't reach my husband on his cell phone. I don't know what's going on. You never think that something like this can affect the world's biggest superpower. It's really, really scary. It really is."

Secretary of Defense Donald H. Rumsfeld was in a wing of the Pentagon opposite the point of impact. He told reporters that he felt the shock and went outside where volunteers were helping to carry away the injured.

Rumsfeld refused to estimate the casualty toll at the military's nerve center. The plane crashed into a newly renovated portion of the building that had not been fully reoccupied.

Authorities estimate that 23,000 people work in the Pentagon, and Rumsfeld vowed that the building would reopen for business today.

Barbara Olson, the wife of U.S. Solicitor General Theodore B. Olson, spoke to her husband twice by cell phone from the hijacked airliner before it crashed.

She told him that all the passengers and crew, including the pilot, were forced to the back of the plane. The only weapons she mentioned were knives and cardboard cutters.