Detectives are investigating the death of a retired Spokane anesthesiologist whose body was found dismembered and burned in the backyard of his Dishman Hills area home.

The victim, Dr. Rex C. Porter, 61, previously worked for Providence Sacred Heart Medical Center. He was the caretaker of his son, Derek C. Porter, 29, who is autistic and nonverbal, according to court documents. They lived on an 11-acre property in the 2800 block of South Park Lane near the Iller Creek Conservation Area.

On Saturday, a neighbor called 911 to report that Porter’s car had been sitting in the driveway for two days with a door open. A garage door had been left open, too.

Spokane County Sheriff’s deputies responded Sunday to the house for a welfare check, according to a search warrant filed Tuesday in Spokane County Superior Court.

Deputies reported seeing the house in disarray as they looked through the windows, including broken glass on the floor. Attempts to call Rex Porter were unsuccessful, prompting deputies to enter the house. They smelled a strong odor they believed to be animal feces, according to court documents.

Deputies continued their search downstairs to the basement and found more glass, along with blood and damaged items. They opened a door and “suddenly an adult male was standing in front of them with only shorts and a T-shirt,” according to court documents.

Deputies detained the individual, believing he was squatting in the house, according to court records.

In the bathroom, the toilet was full of feces and the sink held what deputies thought was the remains of a dead animal, court records stated.

Deputies then determined the man they detained was Derek Porter, Rex Porter’s son who was living in the downstairs bedroom. Derek Porter was taken by medics to Providence Sacred Heart Medical Center, according to court documents.

Deputies reported locating a cut on the bottom of Derek Porter’s foot.

As deputies were leaving the house, a neighbor stopped them and said that if Derek Porter was home, Rex Porter was likely to be home too, according to court records.

Deputies walked the 11 acres of the property and found a fire pit with a human leg partially burned lying near it. When they looked inside the pit, they found a burned head with eyeglasses on it and a torso, according to court documents. The body parts were badly burned, according to court records.

After Derek Porter was checked into the hospital, doctors found what appeared to be blood on his shorts.

The cause and manner of Rex’s death is pending, according to the Spokane County Medical Examiner. Deputies said they have not named a suspect.

One family member said Derek “can be violent and has attacked Rex in the past,” court documents stated. The family member also said Derek’s mother had died years ago and Rex was taking care of him alone.

Detectives are analyzing home-surveillance footage from cameras around the house, according to court documents.

Porter retired a few months ago, according to Jennifer Semenza, spokesperson for the hospital. He worked as an anesthesiologist and operated his own practice in 2013 and 2014.