(Sioux City)– A man who pled guilty to illegal reentry and failure to register as a sex offender was sentenced Thursday (August 6, 2026) to more than a year in federal prison. 27-year-old Sergio Niz-Mendez, age 27, from Guatemala and living in Sheldon, received the prison term after after pleading guilty in March of this year to one count of illegal re-entry and one count of failure to register as a sex offender.
At a plea hearing, Niz-Mendez admitted he was a citizen of Guatemala, that he had previously been removed from the United States in 2018 after serving prison time for a felony conviction in 2016, and that he had not sought permission to legally be in the United States.
He further admitted that due to his 2016 rape of a child with force conviction in Massachusetts, committed when he was 15 years old, he was required to register as a sex offender, which he failed to do while living in Iowa.
In December 2025, Niz-Mendez was found in O’Brien County, Iowa, after he was arrested for operating while intoxicated and eluding.
He must also serve a five-year term of supervised release after the prison term.
Niz-Mendez is being held in the United States Marshal’s custody until he can be transported to a federal prison.
