An unnamed cameraman claims to own a video which shows Madonna and American baseball player Alex Rodriguez having sex together.
The cameraman is apparently demanding £1million for the film, which he says was shot using a hidden camera in an apartment.
According to the Daily Star newspaper, Madonna's lawyers are “aware” of the claims but would not comment further.
The cameraman's claims follow widespread reports in the media linking Madonna to Rodriguez, who recently split from his wife.
A spokesperson for Madonna, who is married to film director Guy Ritchie, has denied the reports.
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