Shain Gandee, the star of the MTV reality series "Buckwild" who was found dead in West Virginia on Monday, died of carbon monoxide poisoning, a spokesman for the Kanawha County Sheriff's Office told TheWrap on Tuesday.
An autopsy found that two other people found in a truck with Gandee -- his uncle, David Gandee, and Donald Robert Myers -- also died of carbon monoxide poisoning.
The manner of death was deemed to be accidental.
Gandee was found with the two other men in a 1984 Ford Bronco that was partially submerged in mud in Sissonville, W.Va, on Monday. The muffler of the vehicle was completely submerged in mud.
The Gandees were last seen at approximately 3 a.m. Sunday at a local bar, and said they were going off-roading in Shain's Bronco, according to the Sheriff's Office.
MTV said Monday that it was "shocked and saddened" by Gandee's death.
"We are shocked and saddened by the terrible news about Shain Gandee, and those involved in this tragic incident," the network said in a statement on MTV.com. "We are waiting for more information but at this time, our main concern is for the Gandee family and their friends. Our thoughts and prayers are with them. Shain had a magnetic personality, with a passion for life that touched everyone he met and we will miss him dearly."
Production on the series, which is going into its second season, has been halted in light of Gandee's death.