Rescue teams continued their around-the-clock search for survivors amid the rubble of the two World Trade Center towers Thursday night, even though no survivors from inside the tower were found Thursday.
Meanwhile, a series of suspicious events kept an anxious nation on edge, collectively serving as a reminder that things have not yet returned to normal. The Capitol was evacuated for less than an hour late Thursday afternoon while Congress was debating President Bush's request for emergency powers in the wake of Tuesday's devastating terrorist attack.
Lt. Dan Nichols of the Capitol police told reporters that a threat had been received and two dog search teams had searched the building. "Based upon two dogs 'hitting' on a package, we went ahead and did do an immediate evacuation of the Capitol to ensure the public safety and the security of the Congress." At 6:18 p.m. EDT, about 45 minutes after the evacuation began, Nichols said that the package had been "cleared" and the building was being reoccupied.
"I haven't seen the senators this close in many years," joked Sen. John McCain, R-Ariz., to CNN during the evacuation.
At the White House, Vice President Dick Cheney was taken to Camp David in Maryland after a threat was made on the presidential residence. Cheney's spokeswoman, Juleanna Glover, said the vice president had been moved as a "purely precautionary measure." The president remained at the White House.
In a further sign of concern, the Lincoln Memorial and Jefferson Memorial also were closed after being reopened earlier in the day for the first time since terrorist attacks earlier in the week.
Also Thursday, the Federal Aviation Administration said the three New York-area airports had been closed because of FBI activity, less than eight hours after they'd reopened, along with many of the nation's other airports. There were reports that seven people had been detained at John F. Kennedy and La Guardia airports, and CNN reported that one man had been arrested at Kennedy for allegedly carrying a false pilot's license.
Two hijacked airliners crashed into the World Trade Center Tuesday, causing the landmark towers to collapse. A third jet hijacked by terrorists slammed into the Pentagon, and a fourth crashed in a field near Shanksville, Pa., in the worst terrorist attacks in American history. The death toll could be as high as 5,000.
President Bush said earlier Thursday that battling terrorism is "now the focus of my administration," and vowed to "lead the world to victory" in the fight.
"Now is the opportunity to do generations a favor by hunting down terrorism," an emotional Bush told an Oval Office news conference Thursday that followed a phone call to New York Gov. George Pataki and Mayor Rudy Giuliani. "Now that war has been declared on us, we will lead the world to victory."
Meanwhile, the FBI said it had found the "black box" flight data recorder of the plane that crashed in rural Pennsylvania Tuesday and was taking it to Washington. At a briefing near the crash site, the FBI's Bill Crowley said debris found several miles from the downed plane was items light enough -- paper, nylon fragments -- to be carried by heavy winds. Crowley said there was no military action against the plane.
And in a bizarre and heartbreaking development in New York, news that five firefighters had been found alive in an SUV that had been buried in rubble since Tuesday turned out to be untrue. The news had lifted spirits among rescuers and around the nation for much of Thursday. Authorities say two firefighters had become trapped in rubble earlier Thursday, and when they were pulled out a few hours later, bystanders had gotten the story confused.
Attorney General John Ashcroft and FBI Director Robert Mueller said Thursday that there were 18 hijackers on the four planes, all of them ticketed passengers. There were five hijackers on each of the planes that crashed in New York, and four hijackers on each of the other two planes that crashed.
Ashcroft said the "number of associates [of the hijackers] was significant," though he would not give a specific figure. Mueller said there had been no arrests in direct connection to the attacks, but several people had been detained and arrested on other state and local charges.
Mueller refused to offer details about the hijackers, but Justice Department spokeswoman Mindy Tucker said their names and photographs of them could be released soon, possibly later on Thursday.
Treasury Secretary Paul O'Neill made encouraging remarks about the economy at a brief press conference. "America's dynamic economy is not located in any one place," he said. "We have every reason to maintain our confidence in the U.S. economy. No evil, no matter how unspeakable, can destroy America's productive spirit."
O'Neill admitted that "this tragedy will cause some short-term dislocations," but said, "These effects will be transitory as transportation flows return to normal."
In New York, the One Liberty Plaza building, across the street from the World Trade Center, appeared on the verge of collapsing, and rescue workers were forced to evacuate the area. A police officer told MSNBC that rescuers had heard tapping from what they thought was a woman trapped in the rubble. It was unclear if the workers had had to abandon that rescue attempt. If One Liberty Plaza collapses, it's expected to take the adjacent Millennium Tower with it.
Aside from One Liberty Plaza, the home of NASDAQ, the American Express building, at 200 Vesey St., was also in danger of collapsing. The Red Cross had set up a makeshift hospital in the American Expresss building, which had to be evacuated because of smoke. One doctor told CNN that in the rush to exit the building, doctors got caught in its revolving doors.
As rescue workers continued their grim task, the weather was expected to become a problem soon. Heavy rains and winds were expected by around midnight.
Giuliani said 4,763 people were missing in New York, including those who were on the two crashed planes. Forty-five people were on the plane that crashed in Pennsylvania and the Pentagon has estimated the death toll there as about 190, including those on the plane. That would bring the death toll near 5,000 if those missing are found to be dead. By contrast, 2,390 Americans died at Pearl Harbor in 1941.
The president said he'd been "on the phone with leaders from around the world who expressed their solidarity with this nation's intention to rout out and to whip terrorism. They fully understand that an act of war was declared on the United States of America. They understand as well that that act could have easily been declared on them."
In a statement, Pakistani President Pervez Musharraf promised the United States his country's "unstinting cooperation." The statement came after Secretary of State Colin Powell on Wednesday asked for support from world leaders -- and focused on Afghanistan and Pakistan in particular, the first for harboring terrorist Osama bin Laden and the second for its proximity to the Saudi expatriate's operations and its own record of support for the Taliban, which controls most of Afghanistan.
Secretary of Defense Donald Rumsfeld told CNN's Larry King that the U.S. has fighter planes on runways, ready to take off on 15 minutes notice. He also said the president is considering calling up reservists.
On Thursday Powell became the first administration official to explicitly state that bin Laden is the prime suspect in the attacks. Other U.S. officials told NBC News that they had irrefutable evidence that bin Laden was behind the attacks.
At a press conference, Deputy Defense Secretary Paul Wolfowitz said the United States will respond to the terrorist attacks with a sustained military campaign.
"It's going to unfold over time," Wolfowitz told reporters at the Pentagon. "One thing that is clear is you don't do it with just a single military strike, no matter how dramatic."
Asked what targets U.S. military strikes might hit, Wolfowitz said, "It will be a campaign, not a single action. And we're going to keep after these people and the people who support them until this stops."
But Powell, pushed by reporters Thursday to define what the administration means by "war," said there are other ways to wage war than militarily, such as with economic measures.
"We have ways of talking to [the Taliban], and we are pursuing them now," he said.
Congress was working to finalize legislation that would provide $20 billion in emergency funds for the president.
"A significant piece of this is going to be used to bring our armed forces to the highest level of preparedness to do whatever the president may ask them to do," Wolfowitz said.
House Minority Leader Richard Gephardt said the president has the power to respond with force without declaring war. "The president under our Constitution has the power to defend people in the United States, and has the power to retaliate against terrorism," Gephardt said.
He also said, "In dealing with this, we will not give up our freedoms. We will have to change the balance between freedom and security, but we will not give up our freedoms."
One way Americans will feel the change in that balance will be at the nation's airports. Transportation Secretary Norman Mineta announced that Americans' ability to travel by air was being restored, but Mineta warned at a news conference that the system "cannot be brought up instantly," that it would take time for the nation's air system to come back up to speed, and that travelers should allow extra time to deal with heightened security measures, such as extra searches, no curbside check-in and no non-passengers in secure areas, which were announced Wednesday.
"In these extraordinary times, we will be vigilant," Mineta said.
Mineta urged passengers to check with airlines on flight schedules and available service. The FAA set up a Web site at www.fly.faa.gov so travelers could check on the status of airports. Planes began flying again in the early afternoon.
House leaders also announced a bill Thursday that would give victims of the attacks and their families tax breaks previously reserved for foreign combat zones.
As the investigation into the attacks continued to focus on bin Laden, German police, acting on a tip from the FBI, detained one man in Hamburg and were seeking another. The police did not say how the detainee might have been linked to the attacks. Federal prosecutors leading the German investigation also said three of the terrorists who died in the suicide attacks were among a group of Islamic extremists they believe founded an organization in Germany that planned attacks on targets in the United States.
But chief federal prosecutor Kay Nehm said there was no immediate evidence of a connection between the organization and bin Laden. Nehm also said that suspected hijackers Mohamed Atta, 33, and Marwan Alshehhi, 23, who are thought to have perished in the crashes, had studied at the Technical University in Hamburg.
Officials didn't release the name or nationality of the detained man, but said he was an employee at the Hamburg airport.
In New York, telephoned bomb threats caused evacuations throughout the morning and early afternoon. La Guardia airport, several high rises in Midtown Manhattan and Grand Central and Penn stations were all evacuated at different times. A bomb threat also forced search-and-rescue workers at the Pentagon to evacuate temporarily Thursday morning. The FBI arrested a man in the incident, a federal official said.
Giuliani said the city of New York had some 30,000 body bags available. Still, he said in the late afternoon that there were just 164 confirmed dead, of whom 46 had been identified. The mayor also said earlier in the day that 70 body parts had been recovered. "I'm sorry that I have to describe it that way," he said at a news conference, "but that's unfortunately the situation that we're facing."
"Let's just say there was a steady stream of body bags coming out all night," said Dr. Todd Wider, a surgeon who was working at a triage center. "That and lots and lots of body parts."
In his televised conference call with Giuliani and Pataki, Bush said he would visit New York on Friday afternoon following a national prayer service at the National Cathedral in Washington. Bush has proclaimed Friday as a national day of prayer remembrance.
Bush also warned Americans against holding all Muslims accountable for the attacks. "Our nation must be mindful that there are thousands of Arab-Americans in New York City who love the American flag as much as you and I do," he said.
Wall Street and the rest of the nation's financial center remained closed for a third day Thursday. The shutdown on the New York Stock Exchange was already longer than the two-day closure at the end of World War II; the longest was for a week after the 1929 market crash. The bond market and commodities markets including the Chicago Board of Trade and Chicago Mercantile Exchange were open for abbreviated sessions Thursday. Bond prices were up sharply, but no panic trading was evident. The New York stock markets were expected to open Monday.
Insurance industry experts say the attack could become the nation's most expensive manmade disaster ever, with payouts ranging from $5 billion to $25 billion.
Giuliani said Manhattan remains closed below 14th Street, but officials hoped to have it open down to Canal Street by midnight Thursday, with limited areas open to create corridors to the Wall Street area.
The vast search to uncover the terrorist plot stretched from Miami to Boston to Portland, Maine, and on to Canada and Germany. Up to 50 people were involved in the attack, the Justice Department said, with at least four hijackers, including Atta and Alshehhi, trained at U.S. flight schools.
America's NATO allies bolstered Bush's case for military action, declaring the terrorist attacks an assault on the alliance itself.
The Federal Reserve, seeking to stabilize the global economy following the attack, announced Thursday that it was making $50 billion available to stabilize European banking systems. The Fed said it was taking the action "to facilitate the functioning of financial markets and provide liquidity in dollars."
In Australia, anger over the attacks in America boiled over into apparent acts of retaliation Thursday as a school bus carrying Muslim children in Brisbane was stoned and vandals tried to set fire to a Lebanese church in Sydney.
Nine Australians are known dead and 85 were among the missing in the wake of the plane crashes. Australian officials also said mosques have been receiving abusive phone calls and anti-Islamic graffiti was found in the Melbourne business district. No one was injured in the attack on the school bus, but "the children are quite shaken up," said Queensland state Islamic Council chairman Sultan Deen.
The sports world has responded with a slew of canceled events. The National Football League, which was criticized heavily in 1963 for playing on the weekend after President John F. Kennedy was killed, announced after several days of agonizing over the decision that it would not play this weekend. Members of the New York Jets had expressed their fear of flying to Oakland for a game.
Major League Baseball announced its games would be postponed for a third straight day, and several minor leagues canceled their playoffs and declared champions or co-champions. Other leagues postponed play, but planned to resume next week. The PGA tour canceled its weekend golf tournaments. College football was a mixed bag. The NCAA announced that conferences and schools could decide for themselves. The Big East conference canceled its games, but the Southeast and Big 12 conferences elected to play, as did many others. The SEC said the weekend's games would "present a meaningful opportunity to bring our people together in a common expression of sympathy and mourning."
A middleweight championship boxing match between Felix Trinidad and Bernard Hopkins, set for New York's Madison Square Garden Saturday night, was postponed.
The Associated Press contributed to this story.