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  1. Homeland Security Investigations (HSI)
  2. News Room
  3. 11 South Dakotans Charged With Online Sex Crimes Following HSI St. Paul Investigation

11 South Dakotans Charged With Online Sex Crimes Following HSI St. Paul Investigation

Release Date: April 24, 2024

SIOUX FALLS, S.D. — On April 5, U.S. Attorney Alison J. Ramsdell announced that a joint online sex crimes operation that ran March 7 through March 12 has concluded with the arrest of 11 individuals.

The operation was conducted by Homeland Security Investigations (HSI) St. Paul, the Internet Crimes Against Children Task Force, the South Dakota Division of Criminal Investigation, the Sioux Falls Police Department, the Watertown Police Department, the Tea Police Department, the Rapid City Police Department, the Minnehaha County Sheriff’s Office, the Lincoln County Sheriff’s Office and the South Dakota Highway Patrol.

Authorities arrested the following individuals from Sioux Falls and federally charged them with attempted enticement of a minor using the internet:

  • Kyle Dean Bult, age 38.
  • Kalvin Michael Frankus, age 37.
  • Hunter Hill, age 22.
  • Stacy Shannon Hoover, age 56.
  • Ryan Nigro, age 32.
  • Jorge Manual Rodriguez-Marroquin, age 47.
  • Dylan Ryan, age 24.
  • Gerber David Santos Gonzalez, age 25.
  • William Danery Sebastian, age 33.
  • Southy Thepmontry, age 69.
  • Carter Lee Tyree, age 20.

The mandatory minimum penalty upon conviction is 10 years and a maximum of life in federal prison and up to a $250,000 fine. The charges are merely accusations, and all defendants are presumed innocent until and unless proven guilty.

“This successful operation shines a bright light on the very real threat child predators pose in our communities,” said HSI St. Paul Special Agent in Charge Jamie Holt. “HSI special agents will continue to fight against the exploitation of children and support victims by providing critical resources and services. Well done to the HSI special agents in South Dakota and our law enforcement community partners for bringing those who prey on our most vulnerable populations to justice.”

“This operation demonstrates the unsettling reality that here in our own communities, there are individuals using the internet to target young girls and boys for sex,” said U.S. Attorney Alison Ramsdell. “We are grateful to our federal, state and local law enforcement partners, who regularly collaborate to safeguard children across South Dakota. May it serve as a stark reminder to parents, guardians and caretakers that the internet can be a very dangerous place for children, particularly when their activity is left unmonitored.”

This case was brought as part of Project Safe Childhood, a nationwide initiative to combat the growing epidemic of child sexual exploitation and abuse, launched in May 2006 by the Department of Justice (DOJ). Led by the U.S. attorneys’ offices and the DOJ’s Child Exploitation and Obscenity Section, Project Safe Childhood marshals federal, state and local resources to locate, apprehend and prosecute individuals who exploit children, as well as identify and rescue victims.

The cases are being prosecuted by Assistant U.S. Attorneys Jeffrey C. Clapper and Elizabeth A. Ebert.

HSI St. Paul oversees suboffices in Minnesota, North Dakota and South Dakota. HSI is the principal investigative arm of the U.S. Department of Homeland Security (DHS), responsible for investigating transnational crime and threats, specifically those criminal organizations that exploit the global infrastructure through which international trade, travel and finance move.

Members of the public can report crimes and suspicious activity 24/7 by calling the HSI tip line at 877-4-HSI-TIP.

Learn more about HSI’s mission to increase public safety in your community on X, formerly known as Twitter, at @HSISaintPaul.

Last Updated: 04/24/2024
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