Gene Hackman and Wife Betsy Arakawa's Causes of Death Revealed

Their dog is still being tested to determine the cause of death, though authorities clarified that dogs cannot contract hantavirus. 

New Mexico County Sheriff's Office deputies had found Hackman, Arakawa and one of their three dogs deceased inside the couple's Santa Fe home Feb. 26 after a neighbor called 911, requesting a welfare check, authorities said.

And while foul play was initially not suspected as a factor in their deaths, an official later stated in a search warrant affidavit, obtained by NBC News, that the circumstances were "suspicious enough in nature to require a thorough search and investigation."

Two maintenance workers told police they found the front door of the couple's home ajar and Hackman and his wife dead inside, the affidavit said, and that deputies "did not observe any signs of forced entry into the home."

Hackman was found dead in a room believed to be a mudroom, the warrant states, with a deputy noting he believes the Superman star may have suddenly fallen. Arakawa was found on the floor of a bathroom, with a space heater near her head and a bottle of prescription pills on the counter with "with pills scattered on the countertop."

Both her and Hackman's bodies showed "obvious signs of death," while hers also showed signs of "body decomposition," the report said. In addition, a deceased German shepherd was found about 10 to 15 feet from the Royal Tenenbaums actor's wife,

in a closet in the bathroom. Their two other dogs were found alive—one was in the bathroom with Arakawa and the other was outside the home.

Police also noted in the warrant that the Santa Fe City Fire Department conducted testing to determine if there were signs of a possible carbon monoxide leak or poisoning and that none were found. Carbon monoxide and toxicology tests were requested for both Hackman and Arakawa and turned out negative, according to the sheriff's department.

Hackman and Arakawa, a classical pianist, married in 1991, and he retired from acting in the early aughts. The actor, whose last role was in the 2004 film Welcome to Mooseport, is survived by his children with late ex-wife Faye Maltese—Christopher Allen Hackman, 65, Elizabeth Jean Hackman, 65, and Leslie Anne Allen, 58.

"It is with great sadness that we announce the passing of our father, Gene Hackman and his wife, Betsy," the actor's daughters and granddaughter Annie wrote in a statement shared with E! News. "He was loved and admired by millions around the world for his brilliant acting career, but to us he was always just Dad and Grandpa. We will miss him sorely and are devastated by the loss."

Look back at Hackman's life in photos...

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