A federal criminal investigation is reportedly probing whether the owner of a Florida anti-aging clinic illegally sold controlled substances to high school students.

The Miami Herald reports that the U.S. Attorney’s Office in Miami is seeking to interview Porter Fischer, the whistleblower who is in possession of 800 pages of the clinic’s records. The development comes after Fischer — Biogenesis’ former marketing director — challenged prosecutors to show interest in the probe.

Porter, in an interview with the Herald, said it wasn’t just baseball players and other professional athletes who received steroids from Biogenesis and its founder, Anthony Bosch, but high school students as well.

Major League Baseball officials had only shown interest in the shuttered clinic’s records, offering Fischer as much as $125,000 for the files. After Fischer declined, Bosch was willing to trade the names of the professional baseball players in exchange for assistance against costly litigation, the newspaper reports.

The push, according to an email obtained by the newspaper, was prompted by a Miami Herald story published last week and a January story in the Miami New Times in which Fischer said Bosch was injecting minors with steroid “concoctions.”

The Coral Gables-based clinic allegedly supplied steroids and other banned substances to at least 20 players, including New York Yankees slugger Alex Rodriguez, who is reportedly facing a lifetime ban if he doesn’t cooperate with investigators.

MLB spokesman Pat Courtney declined comment to the newspaper, but sources said Rodriguez was weighing whether to fight or to cut a deal to avoid banishment.

Michelle Alvarez, a spokeswoman for the U.S. Attorney’s Office in Miami, would neither confirm nor deny the existence of an inquiry.

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