In this file photo dated August 3, 2020, Oklahoma Attorney General Mike Hunter speaks during a press conference in Oklahoma City.
Sue Ogrocki | AP
Oklahoma Attorney General Mike Hunter said Wednesday he would resign, citing the risk of distractions from "personal matters that go public".
Jaeger's sudden resignation, which took effect next Tuesday, came two days after the Republican filed for divorce from his wife Cheryl after 39 years of marriage, The Oklahoman newspaper reported on Wednesday.
The newspaper reported that it "asked Hunter questions Tuesday night about an extramarital affair that the newspaper has confirmed through people familiar with the situation."
"The sources said the affair was with a civil servant who did not work in the attorney general's office," the Oklahoman reported.
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In his resignation statement, Hunter said: "It has been a special privilege to serve as attorney general."
"Unfortunately, certain personal matters that go public are becoming a distraction for this office. The attorney general's office is one of the most important positions in the state government," said Hunter.
"I can't allow a personal problem to overshadow the vital work of lawyers, agents, and support staff on behalf of the Oklahomans."
Hunter communications director Alex Gerszewski declined to provide further details on why the attorney general resigned on a phone call with CNBC.
Hunter became attorney general in 2017 when he was appointed by the governor of the state to succeed Scott Pruitt, who had departed as administrator of the Environmental Protection Agency under then-President Donald Trump.
He was elected for a full term the following year and planned to seek re-election in 2022, according to The Oklahoman.
Hunter last week praised the US Supreme Court for upholding an appeal under a Mississippi bill that allows a woman to obtain an abortion only in the event of a medical emergency or serious fetal abnormality.
Hunter was one of 18 attorneys general who asked the Supreme Court to take the case. He said The Oklahoman could lead to a decision complying with Oklahoma's own restrictive abortion law, which bans the procedure after 20 weeks of pregnancy.