Gene Hackman 'In Good Health' Prior to Death, Says Daughter

Gene Hackman seemingly had no health-related issues prior to his mysterious death ... this according to the late actor's daughter.

Speaking with the Daily Mail, Leslie Anne Hackman says, "there was no indication that there was any problem," leading up to his tragic death. She also notes Gene did not recently undergo any significant surgeries.

While Gene was 95 years old, his daughter claims he was in very good physical condition, participating in activities like Pilates and yoga several times a week -- with his wife, Betsy Arakawa, playing an imperative role in his healthy lifestyle. As we reported, a close friend of Gene's tells us Betsy made sure GH stuck to a strict diet.

Gene's daughter mentions she hadn't spoken with her father in the past few months, although she says they had a good relationship.

Leslie suspects her father and stepmother may have died from inhaling toxic fumes caused by a carbon monoxide leak ... which aligns with what her sister, Elizabeth, told us on Thursday.

In a statement to US Weekly, Leslie also noted she was "anxious to find out what happened" and doesn't know "how long they had been deceased." GH's daughter finds the deaths "very strange" -- adding there's been "no indication of any problem in their house" to her knowledge in all the years they lived in New Mexico.

However, it's worth noting when the fire department inspected the scene they didn’t find any signs of a carbon monoxide leak or poisoning.