Federal police confirmed they were carrying out eight search warrants in five states at the direction of Supreme Court Justice Alexandre de Moraes, who became head of Brazil's top electoral court last week. Police did not name the targets.
Two people with knowledge of the matter, who spoke on the condition of anonymity, said targets of the raids included Jose Isaac Peres, CEO of shopping mall operator Multiplan Empreendimentos Imobiliarios SA, and Meyer Joseph Nigri, chairman of homebuilder Tecnisa SA.
The raids also targeted billionaire Luciano Hang, the founder of department store chain Havan and one of Bolsonaro's most prominent supporters, the sources said.
Multiplan, Tecnisa and Havan did not immediately respond to requests for comment.
Brazilian news website Metropoles reported last week that the businessmen were members of a WhatsApp group that discussed the advantages of a coup d'etat if the far-right leader loses the October election.
Bolsonaro is trailing in opinion polls to leftist former President Luiz Inacio Lula da Silva and has questioned the integrity of Brazil's electronic voting system, stoking concerns that he could challenge the election results.
The sources said businessmen Afranio Barreira Filho, Ivan Wrobel, Jose Koury, Marco Aurelio Raymundo and Luiz Andre Tissot were also targeted in Tuesday's police raids. Reuters was not immediately able to contact them.
(Reporting by Ricardo Brito in Brasilia, Rodrigo Viga Gaier in Rio de Janeiro and Andre Romani in Sao Paulo; Writing by Gabriel Araujo; Editing by Brad Haynes and Chizu Nomiyama)
By Ricardo Brito, Rodrigo Viga Gaier and Andre Romani
