A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. No official explanation was given for the fire, but some local workers said that exhaustion due to overtime work might be one of the reasons. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]

A fire breaks out in Yongding Tower in Beijing's Fengtai district, April 8, 2013, where the Ninth China (Beijing) International Garden Expo will be held. The fire was put out at around 7:15 pm. [Photo/Chinanews.com]