Suspect Arrested After Roommate Fatally Poisoned with Thallium

Sep 4

A 35-year-old St. Cloud man is facing charges after police say he fatally poisoned his roommate with a lethal dose of thallium earlier this summer.

The victim, Cody Ray Ernst, 33, was admitted June 20 to the University of Minnesota Hospital in Minneapolis in critical condition due to the poisoning.

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Doctors determined he had an extremely high and fatal level of thallium in his system and he was not expected to survive.

Two days later, on June 22, Ernst died from complications caused by the ingestion and the St. Cloud Police Department immediately launched a homicide investigation into the source of the poisoning.

Thallium is a naturally occurring heavy metal known for its high toxicity. It’s used in electronics production, low-temperature thermometers and as a medical contrast agent.

The investigation drew assistance from multiple agencies, including police in Fridley and Maple Grove, sheriff’s offices in Pine, Washington and Hennepin counties, the Minnesota Bureau of Criminal Apprehension, the Central Minnesota Violent Offender Task Force, the Hennepin County Violent Offender Task Force and the FBI.

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Investigators say evidence showed that Ernst’s roommate at the time, 35-year-old Stuart William Hanmer, was responsible for poisoning him with the substance.

On Sept. 3, Hammer was arrested in Moorhead and booked into the Stearns County Jail. He remains held there awaiting formal charges.

Anyone with additional information should contact St. Cloud Police at 320-251-1200 or Tri-County Crime Stoppers at 1-800-255-1301.

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