US reality star Shain Gandee died from accidental carbon monoxide poisoning, coroners have ruled.
The 21-year-old Buckwild star and his uncle David were found dead in a car in West Virginia on Monday, just 31 hours after they were reported missing upon failing to return home from an off-road driving trip.
Another victim, whose name has not been released, was also discovered inside the Ford Bronco, which was partially submerged in a mud hole, and now autopsy results have confirmed the three died after inhaling a fatal amount of toxic fumes.
It is not known if the clogged exhaust pipe caused the gas to infiltrate the cabin, but all three deaths have been ruled accidental by officials at the Kanawha County Sheriff's Department.
Funeral arrangements have yet to be announced as Gandee's family is struggling to cover the costs of the memorial. They have appealed for donations from members of the public to put towards the fee.
Network bosses at MTV have suspended production on the show's second season as the cast continues to grieve.