In February 1993, a bomb-loaded vehicle was detonated on the second level within the underground parking structure beneath the World Trade Center in New York City. The blast was so powerful that a crater was formed that penetrated six levels downward. Five people died in the tragedy. Although the blast occurred underground, approximately between the two towers, there was no permanent damage to the towers themselves.
Despite the tragedy, leasing activity largely went unchanged. For example, Bank of America, who had commenced lease negotiations for six floors before the explosion, continued with talks and consummated a lease after the bombing. Some tenants did not renew their leases, but it is unknown if this was related to the bombing.
The property management instituted new and advanced security measures and provided seminars to building tenants regarding these measures. The most noteworthy effect was that all visitors had to show photo ID at a "Visitor's Reception" counter and verify that they have legitimate business within the building. They are then issued a card, which is scanned by a guard at the elevator.