RUNNELLS, Iowa — An Iowa sex offender and a southern Minnesota woman are both facing charges for human trafficking and the alleged sexual exploitation of a minor.

On Friday, Polk County detectives and the United State Marshals Service executed a search warrant at a Runnells home, leading to the arrest of 50-year-old Michael Lee Williams of Runnells, and the filing of arrest warrants for 48-year-old Cynthia Mitteness of Mayer, Minnesota.

Initially, on Thursday, authorities received information from a Carver County Minnesota detective that a sex abuse case happened in Polk County in early June of 2016. The case was originally discovered by the father of a 9-year-old female Minnesota resident after seeing “alarming social media messages” between his wife, Mitteness, and Williams, according to authorities.

The ensuing investigation led to the arrest of Williams Friday on charges of human trafficking, sexual exploitation of a minor, lascivious acts with a child and enticing a minor.

Mitteness was arrested by Minnesota authorities, with warrants for her arrest filed in Polk County on charges of human trafficking, sexual exploitation of a minor, lascivious acts with a child, enticing a minor, and neglect/abandonment of a dependent.

Williams, who is currently being held in Polk County Jail, is a convicted sex offender on the Iowa Sex Offender Registry.