UPDATE: Gene Hackman, Wife Died of 'Natural Causes'

Gene Hackman lived with his wife's body for a week before dying of heart failure in their sprawling mansion.

Haunting new details about the couple's cause of death and tragic last days were announced by a New Mexico medical examiner on Friday.

Arakawa, 65, was believed to have died first on February 11.

Her cause of death was hantavirus pulmonary syndrome, which is caused by contact with rodents like rats and mice, New Mexico's chief medical examiner Dr. Heather Jarrell said.

Hackman, 95, a two-time Academy Award winner, is believed to have died around February 18, the last day his pacemaker reported heart data.

Jarrell identified Hackman's cause of death as hypertensive and atherosclerotic cardiac disease.

An autopsy result revealed that Hackman, 95, also had advanced Alzheimer's, which "significantly contributed" to his death.

“Mr. Hackman showed evidence of advanced Alzheimer’s disease,” Jarrell said.

“He was in a very poor state of health. He had significant heart disease, and I think ultimately that’s what resulted in his death.”

Jarrell said that because of Hackman's advanced Alzheimer's, it is possible he did not know his wife was dead.

The couple's dog, Zinna, was also found dead in a crate in the bathroom near Arakawa's body. Zinna's cause of death was still pending necropsy results, but officials said on Friday that hantavirus is not a possible reason.

Two other dogs were found distressed but alive at the home.

Heartbreaking End

Arakawa's last known movements, as revealed on Friday, began on February 9 when she picked up Zinna from the vet hospital, which could explain why the dog was later found dead in a crate.

Then, on February 11, she took trips to the farmer's market and CVS.

Officials said she was seen on surveillance footage wearing a mask, which could indicate that she wasn't feeling well.

Arakawa had "numerous unopened emails" on her computer from February 11 and no outgoing messages after that date, leading officials to believe she died around then.

She was found collapsed on the bathroom floor before the medical examiner determined she died of hantavirus.

Hantavirus spreads when exposed to rodents' urine, droppings, and saliva, according to the Centers for Disease Control and Prevention.

Symptoms include fever, chills, cough, headaches, gastrointestinal problems, headaches, muscle aches, and fatigue.

Jarrell said it wasn't yet clear how long Arakawa had the virus, or what her symptoms were, before her death.

But New Mexico Sheriff Adan Mendoza said it appeared that Hackman was living in the residence with Arakawa's body for a week until his death.

Data pulled from the actor's pacemaker revealed an abnormal rhythm on February 18, the medical examiner said, which was the last record of heart activity.

He was found collapsed in the home's mudroom with his sunglasses and a cane nearby.

A search warrant revealed that cops noted the legendary actor looked like he fell to the ground suddenly.

His autopsy revealed he had no food in his stomach at the time of his death - but he also didn't show signs of dehydration, the medical examiner said.

Hackman's autopsy also showed evidence of poor kidney function and prior heart attacks, as well as chronic high blood pressure.

He tested negative for hantavirus, Jarrell revealed.

Neither autopsy found evidence of internal or external trauma.

Early Mystery

The heartbreaking news comes after initial autopsy reports revealed the couple had no obvious wounds on their bodies when they died.

The initial report also ruled out carbon monoxide and gas leaks as a potential cause of death.

Several initially confusing details emerged when cops rushed to the scene after a neighborhood caretaker called 911 when he found Hackman and Arakawa unmoving in their home in Santa Fe, New Mexico.

"I'm not inside the house. It's closed. It's locked. I can't go in. But I see them. She's laying face down on the floor from the window," the panicked caller told dispatchers.

When cops arrived at the $3.8 million mansion, they found the door ajar, but there weren't any signs of forced entry.

Near the front of the house, Arakawa was found lying in the bathroom.

An open bottle of pills was scattered on the bathroom counter near her body, cops said.

While officials didn't specify which medicine it was, court records show cops took thyroid medication, diltiazem medication, and Tylenol from the house, according to ABC affiliate KOAT-TV.

Jarrell confirmed on Friday that the thyroid medication had been prescribed to Arakawa and wasn't considered a factor in her death.

Santa Fe County Sheriff Adan Mendoza initially said there weren't any signs of foul play at the scene.

The couple was extremely private in their final years, living in a cul-de-sac of their gated community.

Neighbors who saw the couple walking their dogs in recent years said they were always delighted to see fellow pup lovers, according to The New York Times.

Hackman is survived by two daughters and a son from a previous marriage.