The skybridge also acts as a safety device , so that in the event of a fire or other emergency in one tower , tenants can evacuate by crossing the skybridge to the other tower . The total evacuation triggered by a bomb hoax on 12 September 2001 ( the day after the September 11 attacks destroyed the twin towers of the World Trade Center in New York City ) showed that the bridge would not be useful if both towers need to be emptied simultaneously , as the capacity of the staircases was insufficient for such an event . Plans thus call for the lifts to be used if both towers need to be evacuated , and a successful drill following the revised plan was conducted in 2005
September 11 attacks
September 11 attacks
Petronas Towers