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PARKS, Ariz. - Officials with the Coconino County Sheriff's Office said the cabin where an El Mirage family died had a "significant failure" in the heating system.
CCSO officials announced the finding on Tuesday, after a heating/cooling service provider was employed to investigate the system.
On Monday, CCSO officials said the four people, including two young children, were found dead inside the cabin they were staying in, due to possible carbon monoxide poisoning.
The Coconino County Sheriff's Office stated on Monday the family was found dead inside of a home in Parks, a town located between Williams and Flagstaff. Authorities identified the individuals as 32-year-old Anthony Capitano, 32-year-old Megan Capitano, 4-year-old Lincoln Capitano, and 3-year-old Kingsley Capitano.
According to the statement, CCSO received a phone call from a friend of the Capitano family at 12:26 p.m. Monday, saying family members attempted to contact the Capitanos for a few days with no success, and requested a welfare check on the family.
A deputy arrived at the family home at 1:17 p.m., and called for additional units after smelling a strong odor of gas coming from the home before the bodies were discovered by Ponderosa Fire Department personnel.
"We believe possibly carbon monoxide poisoning malfunction in the heater or any other gas appliance in the residence. We have not determined what that was exactly yet," said Jon Paxton of the Coconino County Sheriff's Office.
CCSO says the investigation is still in its early stages. On Tuesday, investigators were at the cabin all day, testing the appliances to see exactly what might have caused this.
Family, friends react
Family and friends, along with neighbors of the Capitano family, are devastated by the loss.
"When it comes to little people, it's upsetting, but to lose your whole family," said Chrissy Smith. She said she does not know the family personally, but said she wanted to make sure no one bothered the family's home.
"I'm going to monitor it," said Smith. "I'm going to sit in my car and make sure nobody takes nothing. I don't even want them to take a can off that porch. They're going through enough."
Other neighbors who spoke to FOX 10 Phoenix said the Capitanos were a close, tight knit, and loving family.
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The Associated Press contributed to this report.
(NOTE: An earlier version of this story noted the family's surname as "Capitiano", due to an error in the press release issued by the Coconino County Sheriff's Office. CCSO later issued a correction on the surname, and the story was edited to reflect the correct spelling)