The ex-husband of Susan Smith, a South Carolina woman who drowned her two sons in a lake in October 1994, has revealed what his ex-wife said to him after she killed the young boys.

The tragic case received renewed national attention last year after the South Carolina Department of Probation, Parole and Pardon Services in November denied parole for the now-52-year-old woman, who has been incarcerated for more than 30 years after murdering 3-year-old Michael and 14-year-old Alexander Smith.

“She just casually, like you and I sitting here, said, ‘I’m sorry,’ and that was about as far as it went,” David Smith told “Dateline” as part of an episode set to air Friday at 9 p.m. EST. “I would have been around her ankles, begging her to forgive me, if I did what she did.”

David then recalled asking Susan why she killed their two sons. “She said, ‘I don’t know why, but I’m sorry,” David told the show.

Legal identity photograph of Susan Smith. She was convicted on July 22, 1995 of murdering her two sons, 3-year-old Michael Daniel Smith and 14-month-old Alexander Tyler Smith. (Photo by Brooks Kraft LLC/Sygma via Getty Images)

“I know that what I did was horrible. … I’m sorry that I put them through that. … I wish I could take that back, I really do. … I was just scared,” she said. “I didn’t know how to tell the people that loved them that they would never see them again. … I’m sorry, I know that’s not enough … just words, but they come from my heart.”

Pope, along with a former director of the South Carolina Department of Corrections and one of Smith’s former lovers spoke out in Fox Nation’s latest special on the case and Smith’s time in prison, “Susan Smith, The Killer Mom: 30 Years Later.”