Legendary actor Gene Hackman, 95, and wife Betsy Arakawa, 64, and their dog were found dead in their home outside Santa Fe, authorities say.

The deaths of Gene Hackman and his wife, Betsy Arakawa, remain under investigation, Santa Fe County Sheriff Adam Mendoza shared at a press conference Friday afternoon. In a statement, Mendoza stated that both Hackman and Arakawa’s bodies tested negative for carbon monoxide poisoning.

Hackman and his wife, Betsy Arakawa, apparently had been dead for days or even a couple of weeks when investigators found their bodies while searching the couple’s Santa Fe home on Wednesday. Investigators are trying to figure out the last time anyone saw or spoke to them, Santa Fe County Sheriff Adan Mendoza told NBC’s “Today” show on Friday.