New York City is reeling after two hijacked jetliners demolished the twin towers of the World Trade Center Tuesday in attacks President Bush said took "thousands of lives."

The twin attacks on the twin towers came without warning and just minutes apart.

As a local television anchor interviewed an eyewitness to the first crash, a second hijacked jetliner roared into the south tower of the 110-story structure, sending a fireball and clouds of smoke in the sky over New York. "Six or seven floors were taken out and hold on," says one eyewitness. "The building has exploded! You've got people running up the street, let me find out what is going on. Okay, the whole building just exploded, the whole top part. The building is still intact. People are running up the street. Am I still connected?"

Later, both World Trade Towers collapsed, sending untold numbers of people to their deaths. Fire and rescue crews rushed into lower Manhattan to aid the victims as a thick plume of dark gray smoke drifted south of the city, a plume that could be seen from many kilometers away in neighboring New Jersey.

Later in the day, a 47-story building also part of the World Trade Center also collapsed in the aftermath of the terrorist attack.

Hospitals in New York stood by for casualties and an immediate appeal for blood donations was quickly answered by thousands of New Yorkers who lined up to donate, eager to do something in the midst of the carnage.

Manhattan was closed off to incoming traffic and New Yorkers trying to flee the city used any means they could find, including walking over some of the city's famous bridges to try to reach home.

This is not the first time the World Trade Center was the target of a terrorist attack. A truck bomb rocked the complex in 1993, killing six people and wounding hundreds. Six Islamic militants convicted of that attack are now serving life terms in prison.