Sao Paulo - Petrobras shares fell more than 4% on Thursday, declining sharply for a second day after the company released third-quarter results without accounting for a major corruption scandal.
Preferred shares of the state oil giant dropped 4.32% to 8.64 reais at about 13:00 GMT, while ordinary shares lost 5.68% at 8.14 reais.
It followed a 10% drop on Wednesday, after the company released long delayed and incomplete third quarter 2014 results that do not reflect the impact on assets of a massive kickback scandal.
The scandal, which broke in March, involves kickbacks by contractors and payoffs to politicians estimated at as much as $4bn over the past 10 years.
"It shows the company is more disorganised than we thought. So there is no way to know the real dimensions of the problem," Andre Ferreira, an analyst with the Futura brokerage house, told AFP.
Petrobras said third quarter earnings fell 9% year-over-year without taking into account the scandal's impact.
The third quarter results were supposed to have been released in November, but were twice delayed.