An auditorium hosting a campaign rally ahead of Brazil’s upcoming elections partially collapsed on Tuesday, killing nine people and injuring at least 31, authorities said.

The accident happened during a visit to a shipping container company in Sao Paulo state by candidates running for congress and state legislature, officials said.

Congressional candidate Ely Santos and general election candidate Jones Dozinette were among those injured in the crash in the Sao Paulo suburb of Itapecerica da Serra.

Images posted online by state emergency services showed rescuers sorting through the mangled debris of a stage and stands that had been left at near-vertical angles by the collapse.

According to official information, a total of 64 people were present at the time.

“We are making every effort to ensure the rescue operation proceeds as quickly as possible,” Luciana Soares, spokeswoman for Sao Paulo’s state emergency services, said in a statement.

In Brazil, federal and state elections will take place on October 2nd.