A St. Louis grand jury has indicted Missouri Gov. Eric Greitens on a felony invasion of privacy charge related to the Republican's affair with a woman in 2015.

St. Louis Circuit Attorney Kim Gardner announced the indictment Thursday. She launched an investigation in January after Greitens admitted to an affair with his St. Louis hairdresser that began in March 2015. He was elected governor in November 2016.

The woman told her husband, who was secretly taping the conversation, that Greitens took a compromising photo of her at his home and threatened to use it as blackmail if she spoke about the affair. A news release from Gardner says it is a felony if a person transmits an image "in a manner that allows access to that image via a computer."

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