Josh Duggar, a co-star of TLC's 19 Kids and Counting, has confessed to sexually molesting underage girls as a teenager.

Duggar reacted on Facebook to a story first reported by In Touch Weekly.

“Twelve years ago, as a young teenager, I acted inexcusably,” he wrote. “I confessed this to my parents … We spoke with the authorities where I confessed my wrongdoing, and my parents arranged for me and those affected by my actions to receive counseling.”

According to a police report, Duggar allegedly sexually molested 5 girls, some of whom are his sisters, when he was about 14 years old. Jim Bob Duggar, the patriarch of the family, waited nearly a year before reporting his son's actions to the authorities, according to reports.

The 27-year-old Duggar cannot be prosecuted because the statute of limitations has run out.

Duggar has stepped down from his post as executive director of the Christian conservative Family Research Council (FRC), a group vocally opposed to LGBT rights.

Last year, Duggar and his mother, Michelle Duggar, led a successful campaign to defeat an LGBT protections measure in Fayetteville, Arkansas. During an appearance on FRC's Washington Watch radio program, Duggar claimed that such measures jeopardize the safety of children.

In a statement, Jim Bob and Michelle said the incident drew the family “closer to God.”