A sport utility vehicle found with the bodies of an MTV reality show cast member and two others inside was stuck in a mud pit with its muffler below the surface, authorities say.

Buckwild cast member Shain Gandee, 21, his uncle David Gandee, 48, and Donald Robert Myers, 27, were found in the vehicle Monday near Sissonville, W. Va.

mi-220-shain-gandee-0422486

Gandee and the two other men were found in a wrecked vehicle in a remote area. (Amy Sussman/Invision/Associated Press)

The Kanawha County Sheriff's Department said Tuesday that autopsies confirmed they died of accidental carbon monoxide poisoning.

Kanawha County Sheriff's Cpl. B.D. Humphreys said the 1984 Ford Bronco's muffler was below the surface and that mud covered the passenger side. No foul play is suspected.

If the engine kept running when the muffler was blocked, it's possible the cabin of the vehicle could have filled with carbon monoxide from the exhaust.

Humphreys said the trio was last seen around 3 a.m. Sunday at a bar where they told people they were going driving off-road.

Humphreys said state police were getting ready to send out an aviation unit to search for the men when authorities received a call Monday morning that a vehicle was found wrecked in a muddy area a few miles from Gandee's home in Sissonville, about 25 kilometres outside of Charleston.

Authorities found the 1984 Ford Bronco that belonged to the Gandee family in a ditch with all three men inside. Humphreys did not provide details on the condition of the vehicle or the bodies.

The terrain in the Thaxton Hollow area was "very muddy, very rough," Humphreys said, adding that authorities had to use all-terrain vehicles to get to the site.

Kanawha County Commission president Kent Carper said the news was devastating for the small community near Charleston.

"It's a very sad day for the Sissonville area and for these families," he said. "This is a small community, and most of us know directly members of these families. We're keeping them in our hearts and prayers."

mi-buckwild-mtv-promo-300

The MTV reality show Buckwild depicts a group of young people engaged in wild activities, mostly in rural West Virginia. (MTV)

Shain, nicknamed "Gandee Candy" by fans, was a breakout star of the show that followed the antics of a group of young friends enjoying a wild country lifestyle. It was filmed last year, mostly around Sissonville and Charleston.

MTV issued a statement saying it was shocked and saddened to learn of its star's death.

"We are waiting for more information but at this time, our main concern is for the Gandee family and their friends," the network said. "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."

A neighbour, Swanna Frampton, said she had known Shain Gandee since he was a small child.

"He loved to live and have fun. He was a great person," Frampton said. "He did what [the show]

wanted him to do, but he wasn't like that. He was a real person. If you needed help, if needed something, he would come help you no matter what."

MTV series replaced Jersey Shore

Shooting for the second season of Buckwild had begun, but MTV spokesman Jake Urbanski said Monday afternoon it has been suspended. He had no further details.

MTV said the half-hour series in the old Jersey Shore time slot was pulling in an average of three million viewers per episode since its premiere and was the No. 1 original cable series on Thursday nights among 12- to 34-year-olds.

Shain Gandee is the third Buckwild cast member to make headlines.

Last week, 24-year-old Salwa Amin was sent back to jail for violating the terms of her bond following a February arrest. She was charged with two counts of drug possession with intent to deliver and initially jailed on $200,000 bond. That was later reduced to $100,000, but Amin remained behind bars without bond on Monday.

State police say a multi-agency task force arrested Amin and two other people at a Summersville residence after receiving a tip from an informant. A search found oxycodone pills, heroin and $3,000 in cash.

Another cast mate, Michael Douglas Burford, was charged in February with driving under the influence.

Urbanski said none of Gandee's cast mates was available to do an interview Monday, and none immediately planned to issue a statement. But their feelings came through on Twitter, where Ashley Whitt called her friend "the most amazing person I've ever known."

"I know you will be watching over me every time I hit a mudhole. You will always be my best friend, I love you!" she wrote.

Cast mate Cara Parrish and others asked fans to pray for Gandee's parents, Loretta and Dale. "This is the emptiest I've ever felt," she wrote in a tweet.