Hackman, 95, and his wife, Betsy Arakawa, 65, apparently had been dead as long as several weeks when investigators found their bodies while searching the couple's Santa Fe home on Wednesday, said Santa Fe County Sheriff Adan Mendoza.

"Just based on their bodies and other evidence on the body, it appears several days and possibly up to a couple weeks," Mendoza told the "Today" show on Friday morning, when asked about the timing of their deaths.

When asked whether Hackman and his wife died at the same time in their home in Santa Fe or if either passed before the other, the sheriff told the outlet, "I think that's very difficult to determine. I think it's going to be pretty close."

"You know, there's no indication that anyone was moving about the house or doing anything different, so it's very difficult to determine if they both passed at the same time or how close they passed together," Mendonza said. 

"We're trying to put that information together and, obviously, with the assistance of the office of the medical investigator, I think the autopsy report is going to be the key to this investigation."

The Epoch Times' Jack Phillips reports that investigators are also attempting to figure out the last time anyone saw or spoke to them, Mendoza added.

"It's very difficult to put a timeline together even with the help of the office of the medical investigator," he said, adding that Hackman and Arakawa, a classical pianist, were "very private individuals and a private family."

Aside from Hackman and Arakawa, one of their dogs was found dead nearby, according to a search warrant affidavit. A maintenance worker called 911 after spotting the bodies at the couple's Santa Fe home. He reported the home's front door was open when he arrived to do routine work, a detective wrote.

In a recording of the 911 call, though, the worker said he could see Arakawa lying on the floor through a window, but he was unable to get inside.

In the interview, Mendoza noted that there are conflicting accounts about the doors, whether they were locked or unlocked, and said an investigation is underway. Several of their doors were unlocked and a back door was open, allowing two of their other dogs to go in and out, he said, while adding he suspects the front door was unlocked and closed.