SAO PAULO, Oct. 8 (Xinhua) -- One person was killed and eight others injured on Wednesday when an upscale restaurant's roof collapsed in downtown Sao Paulo, Brazil's largest city, according to the Fire Department.

The fatal victim was a female restaurant employee, who was trapped under the rubble for three hours, said the department.

Emergency workers rescued five people from the rubble within two hours of the collapse of the roof and part of the structure of the restaurant. Of the eight injured, four were taken to hospitals for treatment.

The Sao Paulo Security Secretariat initially suspected a gas explosion caused the collapse but later ruled it out, saying only a partial mezzanine collapse occurred and the cause remains under investigation.

At the time of the collapse, 20 people were inside the eatery, a survivor told local media. ■