CARACAS, Venezuela (AP) — A lawsuit has been filed in Florida against Glencore, Lukoil and other international energy companies for their alleged role funneling bribes to corrupt Venezuelan officials in exchange for rigged oil purchase contracts involving state-run PDVSA.

The lawsuit filed by the PDVSA Litigation Trust was unsealed Thursday and alleges the ongoing scheme cheated the Venezuelan company of billions in lost revenue since 2004.

The lawsuit says the alleged bid-rigging was started by two former PDVSA employees living in Miami who set up shell companies in Panama to pay bribes. In exchange, the alleged oil company conspirators gained advantages through the middlemen, including real-time access to highly-confidential information at PDVSA through a "clone server."

Glencore and Lukoil did not immediately comment.

The lawsuit comes amid an intensifying U.S. criminal probe against PDVSA.