The last of four Omaha residents convicted in a sex trafficking ring in Iowa and Nebraska has been sentenced to prison. Twenty-one-year-old Ramon Heredia was sentenced to 11 years in prison after pleading guilty to conspiracy to commit sex trafficking last October.

Heredia’s wife, Katherine, 23, was previously sentenced to three years in prison. Another Omaha couple was convicted in the case. Thirty-five-year-old Edwin “Nate” Horton was sentenced to 14-and-a-half years in prison and his wife, 32-year-old Merrideth Crane-Horton was given a 17-and-a-half-year term.

Investigators say the two couples ran the sex operation from August 2007 through June 2010 in Council Bluffs and Omaha. The prostitutes included a 15-year-old girl.