A man has been charged with murder after his roommate in St. Cloud, Minnesota, died from poisoning earlier this year.

The 35-year-old suspect, who now lives in Fridley, is facing a single count of second-degree intentional murder for the death of 33-year-old Cody Ray Ernst. If found guilty, he could face up to 40 years in prison. 

St. Cloud police say they learned about the poisoning on June 19 after a member of the University of Minnesota police department called them. A pharmacist with poison control said due to the amount of thallium in Ernst's body, it was "likely ingested," since there wasn't any other way to get the same level of exposure through the environment, according to the criminal complaint. 

Ernst died on June 22 from poisoning. 

The month before, the document says Ernst went to the emergency room in St. Cloud, and said he had been smoking the night before, and then experienced "vomiting and seizure-like activity." He had woken up the day he went to the hospital with pain in his chest and abdomen. He was later discharged, but returned the next day with the same symptoms.

The complaint says Ernst indicated that two days before, he started to "feel off" and his symptoms began after waking up and drinking coffee. He also said he had numbness, burning and tingling in his extremities.

Two days later, Ernst left the hospital against medical advice, according to the complaint, but collapsed from pain in the lower half of his body near a bus stop. He then returned to the hospital; however, he was discharged on May 22 after refusing a skilled nursing facility placement, the document says.

The next day, Ernst went to Mercy Hospital but was transferred to the University of Minnesota Fairview Hospital. A metal screening was done on June 15, which showed thallium in his body. Thallium can be toxic to humans.

Police interviewed Ernst's fiancée in late June, who confirmed his illness on May 15 and 16. She also told them she found him in his bathroom and had to do CPR around 7 a.m. on May 16. 

On July 7, the suspect told police he had been living with Ernst, and they would smoke marijuana and drink coffee in the mornings. He said he was upstairs when Ernst had a seizure and didn't know what thallium poisoning was. 

A search was done on the home on Aug. 1, where police found two phones belonging to the suspect, who said he used meth "heavily" around the time he lived with Ernst and wouldn't remember if he searched for thallium, charges say.

Three days later, search history allegedly showed the suspect had searched about thallium toxicity, buying it, how long it would be before the poison would take effect and how much is needed to be fatal. Those searches were done in early April, according to the complaint. 

Court documents say the suspect bought thallium online on April 5 and made two other online orders the following day. All three purchases were made through separate websites. In mid-May, the suspect's internet history showed multiple searches related to thallium, including what temperature it degrades and melts, how it kills someone and if someone would appear to get better after initially being exposed to it.

Police say they found the suspect watched a video showing how to make thallium sulfate multiple times. 

NOTE: The above video first aired on Sept. 4, 2025.