Missouri Gov. Eric Greitens, a rising Republican star, admitted Wednesday to being involved in an extramarital affair in 2015 just before he was elected governor.

St. Louis CBS affiliate KMOV first reported Greitens’ affair, capping a monthslong investigation, after hearing from the ex-husband of the unnamed woman with whom Greitens was involved. The woman's former husband had covertly recorded her admitting to the affair prior to their divorce and he had released the footage to the television station.

Greitens and his wife, Sheena, issued a joint statement together Wednesday night addressing the affair.

“A few years ago, before Eric was elected governor, there was a time when he was unfaithful in our marriage,” the statement said. “This was a deeply personal mistake. Eric took responsibility, and we dealt with this together honestly and privately. While we never would have wished for this pain in our marriage, or the pain that this has caused others, with God’s mercy Sheena has forgiven and we have emerged stronger. We understand that there will be some people who cannot forgive — but for those who can find it in your heart, Eric asks for your forgiveness, and we are grateful for your love, your compassion, and your prayers.”

In the recording, the woman discussed intimate details of her relationship with Greitens, at one point mentioning seeing "a flash through the blindfold" after which she alleged Greitens said: "'You're never going to mention my name, otherwise there will be pictures of me everywhere.'"

Her ex-husband told KMOV that Greitens took a nude photo of her and used it to blackmail her to keep the affair a secret. The woman claimed Greitens told her he later deleted the photo.

Greitens' attorney, James Bennet, later pushed back against the blackmail claim by the woman's ex-husband and said the news station declined to provide the tape or transcript prior to publishing its story. "There was no blackmail and that claim is false," he said.

In a separate statement, Sheena claimed she and her husband have a “loving marriage and an awesome family. Anything beyond that is between us and God. We want the media and those who wish to peddle gossip to stay away from me and my children.”

The Greitens were married in 2011 and they have two sons. Greitens, a former Navy SEAL who previously had been a Democrat, was elected as governor in 2016.