Authorities have completed autopsies on the two victims in the investigation of the mysterious deaths of renowned actor Gene Hackman, his wife Betsy Arakawa, and their dog.

Investigators found no visible injuries on either Hackman or Arakawa, who were discovered deceased in their $3.8 million home in Santa Fe, New Mexico. Their deaths have sparked widespread speculation regarding the cause.

Although the autopsies were finalized early Thursday morning, officials are still awaiting full results, including a toxicology report.

Leslie Anne Hackman, one of Gene’s three children, previously told DailyMail.com that she and her sister Elizabeth Jean suspected their parents might have succumbed to poisonous fumes from a carbon monoxide leak.

However, after the couple’s bodies were found, the Santa Fe City Fire Department and the New Mexico Gas Company conducted thorough tests of the home for carbon monoxide and other hazardous substances but determined that the residence was safe.

An affidavit stated, “New Mexico Gas Company responded to the residence and conducted tests on the gas line in and around the property.”

“At this time, there is no evidence or indication that the pipes in or around the house have ever experienced issues.”

Sheriff Adan Mendoza confirmed in a statement on Thursday afternoon, “Initial findings noted no external trauma to either individual.”