(NewsNation) — The New Mexico Gas Company did not find carbon monoxide or gas leaks in the residence of late Oscar-winning actor Gene Hackman, 95, and his 63-year-old wife, Betsy Arakawa, the Santa Fe County Sheriff’s Office said Tuesday.

Hackman, Arakawa and one of his dogs were all found dead inside their home in Santa Fe, New Mexico, late last month. Two other healthy dogs were located on the property, authorities said.

There were no apparent signs of foul play or external trauma, according to law enforcement.

Since then, the two have tested negative for carbon monoxide poisoning, and no external trauma was evident.

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