The blaze began in the five-story structure at approximately 13:30 when more than 1,000 people were in the store. The store was built with an atrium in the center open to all floors and topped with a skylight, an architecture that behaved like a chimney giving a steady air draft to the store's wooden floors and walls. Cries of "fire!" caused panic, with virtually the entire store engulfed in just 10 minutes. No sprinkler system or other active fire fighting system was present. Many shoppers rushed to windows, since the main stairway was enveloped in thick black smoke, while some jumped to their deaths before fire ladders arrived. Still others went to the roof and escaped via nearby buildings. Some employees, having become used to the exploding fireworks that protestors had set off, ignored pleas to leave the building until it was too late.