Manhattan federal prosecutors have issued a subpoena to the brother of indicted Rudy Giuliani buddy Igor Fruman, CNN reported.

Specifics on what information federal prosecutors are seeking in the subpoena were not immediately available. A spokeswoman for the U.S. Attorney for the Southern District of New York was not available for comment, and Todd Blanche, Fruman’s defense attorney, also did not reply to a request for comment.

Igor Fruman was arrested with his longtime business partner Lev Parnas on Oct. 9 on criminal campaign finance charges at Dulles International Airport as the duo boarded a flight to Vienna.

Parnas and Fruman had worked with Giuliani as he sought to get political dirt on so-called Ukrainian interference in the 2016 elections and on Joe Biden from Ukrainian prosecutors. President Trump allegedly used Giuliani as a backchannel to pressure Ukraine to manufacture political information that would help him in the 2020 elections; that campaign has led to the first impeachment inquiry of the century.

Steven Fruman — Igor’s brother — serves as a vice president at FD Import & Export, his brother’s company, according to securities filings.

Steven Fruman also owns a Woodmere, New York property that his brother, Igor, marked as the address for federal campaign contributions.

Igor Fruman was indicted in part on charges that he made false statements to the Federal Election Commission and that he used Parnas as a cutout to evade legal limits on political giving.

Assistant U.S. Attorney Rebekah Donaleski characterized the investigation in federal court this week as “ongoing,” telling a judge that prosecutors had issued search warrants to multiple premises. CNN reported Friday that the feds blew the door off a safe in the course of the probe.

Separately, Politico reported that the Justice Department’s criminal division had become involved in the investigation, which is reportedly examining Giuliani’s financial dealings.