USA

Thousands of search-and-rescue workers combed through rubble looking for survivors after the World Trade Center buildings collapsed Tuesday in the worst attack on the US since Pearl Harbor. As the Monitor went to press, authorities said they believed there were "a few thousand people" left in each of New York's World Trade Center towers. At the Pentagon, officials estimated between 100 and 800 people died. Another 266 people aboard the four airliners hijacked for the attacks were killed. Seven survivors - six firefighters and a policeman - had been rescued from the Trade Center so far.

President Bush called the attacks an "act of war" from an enemy "different than we've ever faced." He sought emergency funding from Congress to help in the recovery and protect the US's security. Secretary of State Powell promised an American response "as if it is a war," but said the US was "far from selecting any military targets" for retaliation. He was telephoning world leaders, searching for support in a coordinated response. The US military remained on high alert, while aircraft carriers and other Navy ships were deployed along the East and West coasts.

All US financial markets remained closed and uncertainty lingered about when securities trading would resume. Analysts were hesitant to predict the effect the tragedy would have on stocks when trading resumes. The shutdown on the New York Stock Exchange, the US's oldest exchange, was the longest since the market closed for two days at the end of World War II.

With Saudi dissident Osama bin Laden emerging as the most likely culprit for the attacks, investigators at Boston's Logan Airport found a videotape on how to fly commercial jets and other articles meant for - but not loaded on - the plane that crashed into the towers. The evidence was suitcases belonging to an Arab whom police believed might have hijacked one of the planes after arriving on an earlier flight from Portland, Maine. Police said he and at least two other suspects may have entered from Canada.

Civilian air traffic was scheduled to resume "sometime" yesterday, but officials said Logan Airport in Boston would remain closed indefinitely.

Despite the destruction and an outage of power in half the building, many Pentagon employees returned to work as firefighters continue to battle flames near the crash area. Half of the corridors at Defense Department headquarters remain closed and some workers were told to stay home. Congress, and other federal employees also returned to work at other agencies in downtown Washington. Above, residents of the capital pass a military roadblock on 14th Street Northwest.