TPM:

The woman who had an affair with Missouri Gov. Eric Greitens in 2015 told her then-husband that Greitens slapped her against her will, after she told Greitens she had had sex with her husband.

UPDATE: More came:

The St. Louis city prosecutor will conduct a formal investigation into allegations that Gov. Eric Greitens (R) blackmailed a woman with whom he had an affair. “Both parties and the people of St. Louis deserve a thorough investigation of these allegations,” prosecutor Kimberly Gardner said Thursday in a statement. Gardner called the allegations “very troubling.”