In a suspected terrorist attack, two planes crashed into the twin towers of the World Trade Center shortly before 9 o'clock Tuesday morning, causing the collapse of both towers.
President Bush called it an ``apparent terrorist attack,'' and ordered a full-scale investigation. A Palestinian group claimed responsibility, Abu Dhabi television said.
The Pentagon in Washington, D.C., suffered a similar attack, according to news reports.
The World Trade Center was evacuated, as were many other businesses and residences in the lower Manhattan neighborhood. Both the Chrysler Building and Empire State Building were evacuated.
Morning commuters stood on street corners, many of them crying, while they waited for news of the disaster.
Black smoke poured out of two gaping holes in the World Trade Center. Shortly after the plane crashed, a second explosion rocked the other tower. Witnesses said that a second, smaller plane crashed into the tower.
Subway service was suspended, and telephone and Internet lines were jammed.
There were no immediate reports about injuries or fatalities in the disaster.
The World Trade Center, recently purchased by Silverstein Properties, suffered a bombing attack by terrorists on Feb. 26, 1993. The bombing killed six people and injured more than 1,000 others, and led to strict security measures at the buildings.