The blast occurred Friday afternoon at the restaurant called "007" in Sanhe Street of southwest China's Chongqing municipality, a spokesman with the local government told Xinhua.
The cause of the blast was being investigated.
The injured were rushed to hospital, with two in critical condition, the spokesman said.
Chongqing is a major city in southwest China, and one of the four direct-controlled municipalities -- the other three being Beijing, Shanghai and Tianjin.
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