At least eight people died when the wall of an old factory undergoing restoration work collapsed in the southeastern Brazilian city of Sorocaba, officials said.
An undetermined number of people also may be trapped under the rubble of the structure, according to police and firefighters cited by the G1 news portal.
Police spokespersons contacted by Efe confirmed the collapse and said rescue teams had been dispatched to the scene, but they did not specify the number of victims.
The wall, part of a 100-year-old factory being restored as part a shopping center construction project, collapsed Thursday for reasons under investigation in a downtown area used by pedestrians and motorists.
The accident occurred near a viaduct and the largest bus terminal in the city, located in Sao Paulo state, at a time when the streets were clogged with traffic.
The local government deployed all available emergency management personnel to the site to assist in the rescue effort. EFE