Authorities suspect Oksana Grigorieva's sister of leaking recordings of Mel Gibson's rants to RadarOnline.com. Natalie Grigorieva is said to have shopped the tapes to various media outlets, but Radar was the only one that agreed to pay up without hearing them first. "I suspect that if the authorities look at the sister, they'll find a wire transfer or a check to her from the website," a source tells the Hollywood Reporter. The recordings have the family under plenty of scrutiny already: Oksana Grigorieva is being investigated for blackmail.
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