• Kristin Cavallari's brother died of hypothermia.
• There were no signs of major trauma and no suicide note, officials noted.
• Cops did not find any evidence of drugs or alcohol.
Michael Cavallari's cause of death has been revealed as hypothermia and exposure to cold environmental temperatures, according to the Grand County Sheriff's Office incident report shared with The Huffington Post on Wednesday.
The death certificate from the Utah State Medical Examiner's also ruled the death as accidental.
"Michael Cavallari's body was found three miles from where his car was wrecked in the high desert of Grand County, Utah. There were no signs of major trauma and no suicide note," said officials in a statement to E! News. "Cops did not find any evidence of drugs or alcohol either."
"I don't know if he thought he saw lights or something and started walking?" Sheriff Steven White said, via the Associated Press, adding that his office is still waiting on toxicology reports. "We just don't know."
Michael, the 30-year-old brother of reality star and author Kristin Cavallari of "The Hills" and "Laguna Beach," was found dead in Utah on Thursday, Dec. 10. Michael's body was located by search crews at 10:30 a.m. in a "steep and very rocky area."
At the time, Kristin issued a statement to People magazine, saying:
We want to thank everyone for their love, support and prayers during this very difficult time. We have just been informed by the authorities my brother's body has been found. This is a very painful time and we are still processing it all. We kindly ask everyone please respect our privacy during our time of grieving.
The reality star later posted a photo of herself and her deceased brother on Instagram, captioning it:
"My heart is in a million pieces. Mikey, I could always count on you to make me laugh. You had such a good heart and will be forever missed. I'm at a loss for words but I know u are in a better place and finally at peace. I love u so much RIP."
Michael was first reported missing on Nov. 27, when his abandoned 2014 Honda Civic was found on the side of the road in Grand County. The vehicle was registered to Michael Cavallari of San Clemente, CA, and nearby security footage from a convenience store also positively identified Cavallari in Utah. At the time, no foul play was suspected.
"There's really no signs of anything," Sheriff Steven White of the Grand County Sheriff's Office said on "Today" show. "The vehicle was just abandoned."
The Huffington Post reached out to Kristin Cavallari and will update this post accordingly.
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