Associates of Dmitry Firtash, a Ukrainian oligarch wanted by U.S. authorities on conspiracy charges, reportedly worked to find dirt on former Vice President Joe Biden last year as part of an effort to enlist Rudy Giuliani’s help with the oligarch’s legal case. According to Bloomberg, Firtash—who is based in Vienna, Austria, and fighting extradition to the U.S.—hired pro-Trump lawyers Joe diGenova and Victoria Toensing earlier this year. DiGenova and Toensing both have worked with Giuliani to get opposition research on Biden and have been vocal in their support of Trump. They reportedly charged Firtash about $1 million for their work. Around the time DiGenova and Toensing were hired, Firtash’s associates began using their network in Ukraine to get dirt on Biden, and were able to get a witness statement from ex-Ukrainian prosecutor-general Viktor Shokin—the same one held up by Giuliani on Fox News as proof of Biden's supposed corruption.

DiGenova and Toensing reportedly also charged Firtash for the work of Lev Parnas, a Giuliani associate, as a translator and contact, a source told Bloomberg. Another Giuliani associate, Igor Fruman, also helped DiGenova and Toensing in their law practice, his lawyer John Dowd said. Parnas and Fruman were recently charged with violating campaign finance laws and were arrested at an airport before boarding a one-way trip to Vienna. Firtash has denied having contact with Giuliani. Giuliani told Bloomberg that he had “nothing to do with Firtash case” and claimed he “never met him.” Toensing, diGenova, and the Justice Department all declined to comment.