(CNN) The former lead detective handling the New York sex crimes investigation against Harvey Weinstein told an accuser to delete cell phone messages prior to turning her phones over to authorities, according to the Manhattan District Attorney's Office.

NYPD Detective Nicholas DiGaudio advised the woman that she should delete "anything she did not want anyone to see before providing the phones to our office," according to a letter from the DA's office to Weinstein's attorney, Benjamin Brafman.

The three charges against Weinstein relating to the woman include predatory sexual assault, rape in the first degree and rape in the third degree, stemming from a March 2013 incident.

The district attorney learned of the incident from the complainant's attorney last week, after DiGaudio was accused of coaching a witness . The detective is now the subject of an internal NYPD investigation and removed from the Weinstein case. DiGaudio could not be reached for comment.

It's unclear what the revelation may mean to the case, but the NYPD maintains the evidence against Weinstein is "compelling and strong."

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