A Spokane anesthesiologist who was found dismembered and burned in his backyard in the Dishman Hills area in April died as a result of an accident, according to the Spokane County Medical Examiner’s Office.

Dr. Rex Porter’s cause of death was ruled probable from cardiac dysrhythmia due to a combined drug toxicity caused by a simultaneous use of alcohol and prescription medication including sertraline, trazadone and ziprasidone, according to the medical examiner.

Sertraline, also known as Zoloft, treats depression, obsessive-compulsive disorder, panic disorder and other mental issues. Trazadone is a drug that treats depression, and ziprasidone treats schizophrenia and bipolar disorder.

The Spokane County Sheriff’s Office closed the investigation into Porter’s death following the results, said spokesman Cpl. Mark Gregory.

“We found no evidence of any criminal acts leading up to his death,” said Gregory.

Deputies found Porter in his backyard fire pit on April 6. Some of his limbs were detached and his body was burned, according to court documents. He was 61.

Gregory did not disclose why or how Porter’s limbs had been separated and his body burned.

Deputies originally conducted a welfare check at Porter’s house in the 2800 block of South Park Lane near the Iller Creek Conservation Area after neighbors reported that Porter’s car and garage doors were open for days.

Deputies found broken glass and furniture damaged in the house. They searched it and reportedly found Porter’s son, Derek Porter, who is autistic and nonverbal, in a downstairs bedroom with a cut on his foot and blood on his shorts.

Thinking he was squatting in the house, deputies detained him. They soon discovered that Derek Porter was Rex Porter’s son and transported him to a hospital. Detectives did not name him a suspect.

When deputies were leaving the residence, a neighbor met them outside and told them that Rex Porter had to be there, because he was Derek’s caretaker.

Deputies searched the 11-acre property and found Rex Porter’s remains, according to court documents.

Detectives seized camera footage from around the house, but police have released no information about what the footage showed and have not reported finding any weapons or tools related to the dismemberment.

The Sheriff’s Office declined a Tuesday request for further documents relating to the investigation into Porter’s death.

The Spokesman-Review reached out to Rex Porter’s family but did not immediately hear back.