SAO PAULO, Sept 29 (Reuters) - Shares of Brazilian state-run companies plunged on Monday after an election poll released late Friday showed President Dilma Rousseff gaining on challenger Marina Silva ahead of Sunday's election.
Brazilian investors have been heavily critical of Rousseff's government for enacting policies that have gone against minority shareholder interests in state-run companies.
At 10:19 a.m. (1319 GMT), shares of state-run oil producer Petroleo Brasileiro SA, known as Petrobras, dropped nearly 11 percent, while shares of power utility Eletrobras fell over 6 percent. Share of state-run lender Banco do Brasil SA fell over 9 percent.
The broader benchmark Bovespa index dropped 5.37 percent to 54,142.91, its biggest intraday decline in over three years. (Reporting by Asher Levine Editing by W Simon)