MINNEAPOLIS >> A poison specialist and former medical resident at Mayo Clinic in Minnesota is charged with fatally poisoning his wife, a 32-year-old pharmacist who died days after she went to a hospital in August with stomach distress.

Authorities say Connor Bowman, 30, tried to stop the autopsy on his wife, Betty Bowman — arguing she should be cremated immediately and claiming she had a rare illness, which hospital tests did not confirm. The medical examiner’s office halted the order for cremation, citing suspicious circumstances, according to a criminal complaint, and an autopsy showed Betty Bowman died from toxic effects of colchicine, a medicine used to treat gout.

Medical records indicate she was not diagnosed with gout and had not been prescribed the medicine, the complaint states, adding that Connor Bowman had been researching the drug prior to his wife’s death. Six days before she was hospitalized, he had also converted his wife’s weight to kilograms and multiplied that by 0.8 — with 0.8 mg/kg considered to be the lethal dosage rate for colchicine, according to the complaint.

Connor Bowman was charged Monday with second-degree murder. He was arrested Friday and was still in custody as of Tuesday. His attorney did not immediately respond to requests for comment from The Associated Press.

Mayo Clinic spokesperson Amanda Dyslin released a statement Tuesday that did not identify Bowman by name, but indicated he was a resident at the hospital.

“We are aware of the recent arrest of a former Mayo Clinic resident on charges unrelated to his Mayo Clinic responsibilities. The resident’s training at Mayo Clinic ended earlier this month,” the statement said. Dyslin did not say why Connor Bowman’s training at Mayo Clinic ended.

Betty Bowman was also a pharmacist at Mayo Clinic.

According to the criminal complaint, the Southeast Minnesota Medical Examiner’s Office alerted police to the “suspicious death” of Betty Bowman on Aug. 21, a day after she died.

She had been admitted to Mayo Clinic Hospital, Saint Marys, in Rochester on Aug. 16 with “severe gastrointestinal distress and dehydration where her condition deteriorated rapidly,” the complaint said. Her initial symptoms were similar to food poisoning and were treated that way, but they continued to worsen. She experienced cardiac issues, fluid in her lungs and organ failure.

While Betty Bowman was in the hospital, Connor Bowman suggested she was suffering from a rare illness called hemophagocytic lymphohistiocytosis, or HLH. Hospital tests came back inconclusive for HLH, but Connor Bowman told multiple people that she died from that disease, according to the complaint.

He also told the medical examiner’s office that Betty Bowman’s death was natural and that she “did not want to be a cadaver,” and therefore, the autopsy should be canceled, the complaint said. He asked an investigator at the medical examiner’s office if the toxicology analysis would be more thorough than the analysis done at the hospital.

The night before Betty Bowman went to the hospital, she told a man — identified as SS in the complaint — that she was drinking at home with Connor Bowman. The next morning, she told SS she was sick, possibly from a drink that was mixed into a large smoothie.

Connor Bowman was a poison specialist and answered calls about poisons, using devices from the University of Kansas for his work, according to the complaint. A woman from the University of Kansas told investigators that Connor Bowman had been researching colchicine, the drug used to treat gout, though he had not received any calls about colchicine, nor had any other employees.

Investigators found that Connor Bowman had searched “internet browsing history: can it be used in court?” and “delete amazon data police” on Aug. 5. He did calculations that match the lethal dosage rate for colchicine on Aug. 10.

The Minnesota Department of Health found colchicine in Betty Bowman’s blood and urine samples that were taken at the hospital, and the medical examiner determined the cause of death to be toxic effects of colchicine, the complaint says.

One woman told investigators that the Bowmans had been talking about divorce, and another told authorities that Connor Bowman said he was going to get $500,000 in life insurance from his wife’s death, the complaint says. Authorities found a receipt for a $450,000 bank deposit inside his home.

He is scheduled to appear in court on Nov. 1.