ST. LOUIS – Missouri Gov. Eric Greitens is blaming his felony invasion of privacy indictment on a "reckless liberal prosecutor," holding fast to the assertion that any case stemming from his admitted extramarital affair is politically driven.

The Republican governor and St. Louis' Democratic circuit attorney, both just a little more than a year into their offices, certainly are political opposites. But a growing number of GOP lawmakers on Friday were questioning whether Greitens can continue to effectively lead while facing the indictment.

The indictment – handed down by a grand jury and stemming from an investigation launched by Circuit Attorney Kim Gardner – alleges that Greitens took a compromising photo of a woman without her consent and transmitted the image to a computer. Greitens has admitted being unfaithful to his wife before he won election as governor but has denied criminal wrongdoing and has insisted that the affair with his former hairdresser was consensual. His attorney filed a motion to dismiss the indictment.

Greitens claims the criminal case is politically motivated.

"The people of Missouri deserve better than a reckless liberal prosecutor who uses her office to score political points," Greitens said in a statement Thursday.

Gardner didn't respond, but her spokeswoman Susan Ryan said the prosecutor "will not be playing political games during this process."

"These personal attacks, while disappointing, will not distract her from her duty to serve justice and the citizens of this community," Ryan said Friday.

While the state Republican Party was still supporting Greitens, some lawmakers, including some Republicans, were calling on him to resign or face legislative impeachment proceedings.

"In the wake of the grand jury criminal indictment, and with legal proceedings to come, I cannot see how he could effectively perform the duties of his office, let alone to lead with the kind of moral authority needed to make a positive impact," said Sen. Kevin Corlew, of Kansas City, one of at least four Republicans who were newly calling for Greitens' resignation.

Senate Majority Leader Mike Kehoe, a Republican from Jefferson City, said the indictment "causes me to question whether the governor has the ability to effectively lead the state going forward," but he stopped short of calling for Greitens' resignation.

Other Republicans remained reserved in their judgment but expressed support for a legislative investigation into Greitens announced Thursday by GOP House leaders. An investigation is a necessary first step before an impeachment proceeding but does not necessarily lead to one.

Former Missouri Supreme Court Chief Justice Mike Wolff said it's up to the House to decide whether a state official can be impeached for conduct that occurred before he took office.

The only statewide Missouri official to be convicted, impeached and ousted from office was Democratic Secretary of State Judy Moriarty in 1994. She was convicted of a misdemeanor for backdating her son's candidacy paperwork for a state House seat, then later impeached by the House and removed by the state Supreme Court.

The prosecutor pursuing the case against Greitens was once a Missouri House member herself, serving two terms starting in 2012. Gardner came to politics after serving as a prosecutor in the circuit attorney's office under her predecessor, Jennifer Joyce, from 2005 to 2010.

Missouri Republican Party executive director Sam Cooper called the indictment of Greitens a "political hit job."

But Democratic Rep. Alan Green of St. Louis County, chairman of the Missouri Legislative Black Caucus, defended Gardner, nothing that it was an independent grand jury that "found probable cause to indict the governor."

The circuit attorney is an elected official. Gardner's office reviews up to 13,000 cases brought by police each year and files charges in roughly half of them, Ryan said.

Gardner, who grew up in St. Louis and earned a law degree from St. Louis University, decided to run for the job leading an office of about 60 prosecutors when Joyce opted not to seek a fifth term in 2016. With unrest in nearby Ferguson still on the minds of people in St. Louis, where black residents slightly outnumber whites, Gardner, who is black, pledged to restore trust in the criminal justice system.

Gardner, 42, defeated three other Democrats in the August primary, aided by $200,000 in late donations from a national super PAC partly funded by liberal billionaire George Soros.

The indictment has Greitens at a standstill. He canceled plans to go to Washington this weekend for a National Governors Association meeting, and the Republican Governors Association said Greitens "no longer intends to serve" on its executive committee.

The indictment states that on March 21, 2015, Greitens photographed a woman identified only by her initials "in a state of full or partial nudity" without her knowledge or consent. The indictment said Greitens "transmitted the image contained in the photograph in a manner that allowed access to that image via a computer."

Soon after the affair began, the woman's husband secretly recorded a conversation in which she described the alleged incident. She said on the tape that Greitens invited her downstairs at his home because he wanted to show her "how to do a proper pull-up."

She said Greitens "taped my hands to these rings and then put a blindfold on me," took a photo of her partially nude, then warned her to remain silent.

"I saw a flash through the blindfold and he said, 'You're never going to mention my name,'" she said.