Gene Hackman death: What the investigation tells us so far

Questions continue to swirl as investigators probe the deaths of actor Gene Hackman, his wife, Betsy Arakawa, and one of their dogs. 

Hackman, 95, was a prolific actor who performed as an array of heroes and villains in films including "The French Connection," "Hoosiers" and "Superman" from the 1960s until his retirement in the early 2000s.

Arakawa, 63, was a purposely private person and classical pianist who first met Hackman while she was working part-time at a fitness center in the mid-’80s, according to The New York Times.

RELATED: Who was Betsy Arakawa, Gene Hackman's wife?

What happened to Gene Hackman and Betsy Arakawa? 

What we know:

In a search warrant affidavit obtained by Fox News Digital, officials revealed that Arakawa's body was found decomposed with bloating on her face and mummification in her hands and feet. Hackman was also found to have the same signs of decomposition as his wife.

When two Santa Fe County patrol deputies arrived at the scene, they walked to the front of the residence and found the front door ajar. They did not observe any signs of forced entry into the home, according to the warrant.

Hackman's body was discovered in the home's entryway and Arakawa was found dead next to a space heater in a bathroom. On a countertop near Arakawa, pills were scattered next to an open prescription bottle, according to the search warrant.

Police said they found the body of a German shepherd in the bathroom closet. Two other dogs were found alive on the property.

No foul play was suspected, authorities said, though a search warrant showed investigators thought the deaths were "suspicious enough in nature to require a thorough search and investigation."

Death investigation update

The Santa Fe Sheriff's Office provided a brief update on the investigation Friday afternoon, but had little new information to add. 

The most notable new details were: 

• Both Hackman and Arakawa tested negative for carbon monoxide.
• Investigators say the "last event" on Hackman's pacemaker was recorded on February 17, giving some clue as to his time of death.
• An initial autopsy revealed "no external trauma" to either victim.

What we don't know:

Their cause of death is still unclear, as is the question of who died first. 

Former NYPD cold case investigator Joseph Giacalone questioned the color of the skin on the decomposed bodies, which wasn't noted in the search warrant affidavit.

"Was the house really hot? Did they have a lot of clothes on? The heat can get the bodies into those stages faster," Giacolone said.  "You have different stages that you look for, like the livor mortis, which is the purple-ing of the body, and what we call the dependent areas you could tell by how long somebody has been dead. This is all approximate stuff."

He added, "How long have the bodies been there? You can generally determine this based on the stiffness that you see. So, from an investigator's standpoint, there are clues. This is something, ultimately, the medical examiner or medical legal investigator will weigh in on. But detectives generally have a good idea about what they're looking at."

What does Gene Hackman’s family say? 

Dig deeper:

Elizabeth Jean Hackman, Gene Hackman’s daughter, told TMZ they aren’t sure what happened, but they believe the cause might be from toxic fumes.

However, the New Mexico Gas Co. tested gas lines at the home but didn't find any signs of problems at the time, according to the warrant.

What about the Sante Fe estate where they were found dead? 

The backstory:

Hackman and Arakawa had owned the sprawling property in the Hyde Park area near Santa Fe since the '80s, according to Realtor.com.

It reportedly has a value of $3.8 million.

The 12-acre property has two homes, one of which existed when Hackman bought the property and another he had built about 25 years ago, Fox New Digital reports. 

A caretaker for the subdivision where the home is located called 911 after discovering their bodies. 

Forensics experts weigh in 

What they're saying:

"We've heard about pills being scattered about, and pills being scattered about and pills being ingested are completely different," former forensic death investigator Joseph Scott Morgan said in an interview with Fox News. 

Morgan said he was also interested to know more about the space heater which was found nearby Arakawa's body, in addition to a test for the carboxyhemoglobin levels.

"Not just on Mr. Hackman and his wife, but also, I would imagine, somebody involved in veterinary medicine will also attend to this dog as well, to see if there is any carbon monoxide in their system regardless of what the fire department says about what was there and what wasn't there," Morgan said.

"You have to be very thorough, very painstaking in this case. They'll do full-body X-rays, they'll do exhaustive external examinations before they ever do a full autopsy."

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