Brazil’s epic “Car Wash” corruption investigation has extended to four of the world’s largest oil trading companies – Vitol SA, Trafigura, Glencore PLC and Mercuria Energy Group.

And one of the pending transactions to be affected is the sale by Brazil’s state-owned oil firm, Petrobas of its stake in some Nigerian oil fields.

Vitol is leading a consortium to buy the Petrobas interest for $1.5 billion.

Brazil’s Federal prosecutors allege the European multinationals and some smaller players collectively paid at least $31 million in bribes over a six-year period to employees at Petrobras to sell them oil at sweetheart prices.

They said the firms’ top brass had “total and unequivocal” knowledge that they were fleecing Petrobras and that the illicit activity may still be ongoing.

More than 600 pages of legal documents reviewed by Reuters portray what prosecutors describe as a bustling criminal enterprise fuelled by creativity, competition and greed.

Authorities say the trading companies often used freelance middlemen in an effort to cover their tracks, allowing these businessmen to negotiate deals and pay off Petrobras collaborators using bank accounts in several countries.

Emails obtained by investigators show intermediaries hustling to profit from their connections, authorities said. Some shared spreadsheets divvying up to the last cent their cut of the spoils from deals they allegedly sealed with crooked Petrobras employees.

Prosecutors said the messages also show that rings of middlemen knew about one another and battled fiercely for the favor of the big oil-trading firms. Some discussed their attempts to woo top executives with promises of delivering more shady trades and fatter profits than rivals.

One intermediary griped that Vitol was “not at all sentimental” and would choose whomever could secure them the biggest returns.

“Now you are the flavour of the month, next month there is a new flavour,” the middleman lamented in the email.

Brazilian authorities last week searched the Rio de Janeiro-area offices of Vitol, Trafigura and Glencore as well as other entities they allege participated in the scheme. Police said they could not locate a physical office in Brazil for Mercuria. No charges have been filed. (NAN)