The first outside recruit to join the ruling party's presidential election campaign committee resigned from her post just days after being appointed, over allegations surrounding a past marriage.

Cho Dong-youn, a professor of military studies at Seokyeong University, hinted late Thursday that she would resign from her post as a co-chair of the election campaign committee for the ruling Democratic Party of Korea's presidential nominee Lee Jae-myung.

She said she was marred by accusations and denouncements over her personal life for the past two days following her appointment announced Monday. Cho added she is "sincerely thankful and sorry," ending her post with "goodbye."

"I have always maintained balance however difficult it was, but now I honestly don't know what to do," Cho said in a Facebook post late Thursday, which was deleted hours after being posted.

"But I must ask to leave my children and family out of this. I will carry this on my shoulders, so I ask to stop making the lives of my innocent family members difficult."

Democratic Party Chairman Song Young-gil confirmed in a meeting with the press Friday that Cho expressed her intent to resign in a phone conversation with him in the morning.

The election campaign committee said in an announcement later that Song decided to accept Cho’s resignation to prioritize protecting her children from "murderous attacks" after consulting with Lee.

Song was instrumental in recommending Cho for the election campaign post, highlighting her status as a working mother with a successful academic and military career. He denounced the press for overly reporting on her personal life, despite her not being considered for any public office roles.

"I ask the people to contemplate whether it is appropriate to wage attacks on (Cho’s) family and personal life based on the fact that she got a divorce 10 years ago, even though she is not immediately being considered for any public office roles or running for a lawmaker seat," Song said.

"Whatever the case may be, (Cho) has lived a difficult life as a woman with two children. And beyond her life as a wife and a mother of children, she fiercely worked to carve out her own social life by herself."

Cho, a 39-year-old retired Army officer now in academia, was named the first outside recruitment pick for the Democratic Party’s presidential election team Monday. The Democratic Party credited her as a defense expert with a specialty in aerospace and defense.

She graduated from the Korea Military Academy in 2004 and spent her military career serving in various roles for the Zaytun Division in Iraq, ROK-US Combined Forces Command, the Republic of Korea Army Headquarters and the Ministry of National Defense until ending her service as a major in 2020.

Cho earned her master’s degree in public administration at the Harvard University John F. Kennedy School of Government and was selected as a World Fellow at Yale University in 2018. She has been serving as the director of the Center for Future Defense Technology and Strategy at Seokyeong University.

Her appointment to the campaign role came under question immediately with media personality and lawyer Kang Yong-suk revealing that Cho had a child born out of wedlock during her marriage with her first husband. Kang called on her to resign by revealing legal documents along with his claims.

It was confirmed that Cho lost a suit against her former husband in 2014, who claimed her second child was not genetically related to him. Since then, a large portion of Cho’s personal life has been made public, including the names and details of family members and relatives.

Song warned that he would have his party’s legal support team file a complaint against Kang for his actions, saying he had crossed a line by depriving Cho of her basic rights with his “heinous criminal acts.” The legal team filed the complaint to the prosecution shortly after.

"What sins have these children committed?" Song asked in a meeting with reporters. "We can’t categorize the vile act of revealing the faces and names of the children as actions deemed appropriate for the press."

Lee offered apologies to Cho, saying she was scarred after joining his team with a bid to drive positive changes. He asked the public to be "considerate" and refrain from inflicting pain on her and her family.

"This is really unfortunate, and I say this with a heavy heart," Lee said in a Facebook post Friday. "She and her family were inflicted with huge scars after she tried to join hands with me with a determination to change the world. I am sorry for co-Chair Cho Dong-youn and her family."

The ruling party has meanwhile been criticized for not being careful in examining Cho’s background before bringing her on to the campaign, as most of the claims involving Cho were found to be true despite many repudiations from party officials that "most of the accusations" were false.

Rep. An Min-suk, a press relations official with Lee’s presidential campaign, said earlier that all of the accusations made about Cho’s personal life were found to be false, adding her story is exemplary and "perfect."

The incident is a damaging event for Lee’s presidential campaign, as Cho's intent to resign harms Lee’s emphasis on novelty and change in differentiating himself from the Moon Jae-in administration, which has also endured criticism for personnel appointments over the past four years.

A significant number of Moon’s picks for ministerial and public official posts have been brought under question due to controversies surrounding their past behaviors and personal interests.