Robert Mueller’s FBI strikes again.

Multimillionaire pedophile Jeffrey Epstein secretly served as a “key federal witness” against two hedge fund managers around the time he cut the sweetheart deal that let him avoid federal child sex-trafficking charges and serve just 13 months in a Florida jail, according to a new report Wednesday.

A year-long investigation by the Miami Herald turned up records that show Epstein — who was one of the fund’s largest investors — cooperated in the prosecution of a pair of executives at now-defunct Bear Stearns financial firm and received “valuable consideration” for providing investigators with unspecified information.

Emails also show then-Miami US Attorney Alexander Acosta — who is now President Trump’s secretary of labor — and the lead prosecutor in the case agreeing to help Epstein’s high-powered defense lawyers try to contain the scandal sparked by his 2006 arrest in Palm Beach, according to the Herald.

“On an ‘avoid the press’ note…I can file the charge in district court in Miami which will hopefully cut the press coverage significantly. Do you want to check that out?” Assistant US Attorney Marie Villafana wrote in September 2007 to defense lawyer Jay Lefkowitz, a former colleague of Acosta’s at the Kirkland & Ellis law firm.

The following month, Acosta met with Lefkowitz for breakfast at a Marriott hotel in West Palm Beach — 70 miles from Acosta’s office — to negotiate terms of Epstein’s non-prosecution agreement with the feds, according to the Herald.

Once the pact was struck, Epstein — who’s hosted former President Bill Clinton, British Prince Andrew and others at his own private Caribbean Island — pleaded guilty to two felony prostitution charges in state court, even though the feds identified 36 underage girls who accused Epstein, then a powerful pal of Clinton and Prince Andrew, of sexually abusing them in his Palm Beach mansion between 2001 and 2005, the Herald said. READ MORE: