Iran Press/ Asia: Preliminary investigation suggested that a gas leak had caused the explosion in the cafeteria and collapsed the building in the Wulong District of Chongqing city.
As of midnight on Friday, 26 people had been taken from the site, 16 of whom had died, the state broadcaster CCTV reported on Saturday.
One person was in critical condition, and the other injured people were also in hospital after being trapped in concrete following the explosion.
A team of more than 600 rescue personnel and firefighters was dispatched to the scene.
Chongqing, with a population of over 30 million and with an area of over 82,300 square kilometers, is China's biggest city by far.
Such incidents are not uncommon in China. On Monday, a landslide at a construction site in southwest China's Guizhou province killed at least 14 people.
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