GREEN RIVER, Wyoming (KTVX) Three people are dead following a multi-vehicle crash in the westbound tunnel of I-80 in Green River, Wyoming, on Friday, according to the Wyoming Department of Transportation.

The crash and apparent fire were first reported around noon on Friday. The WYDOT shared traffic camera photos showing thick black smoke billowing out of the westbound tunnel as traffic piled up. Active fire in the tunnel initially delayed the investigation as fire crews were still battling spot fires in the tunnel by 9:30 p.m. that night.

Few additional details about the fiery incident, including what may have started it, have been released.

Authorities have determined the Valentine’s Day crash involved “multiple passenger and commercial vehicles in the middle and western parts” of the tunnel. The Green River Tunnels are located along I-80 under Castle Rock, a snow-covered sandstone formation that looms over the town of Green River in the state’s southwest, roughly 270 miles west of Cheyenne.

WYDOT confirmed two deaths early into the investigation. On Sunday, authorities confirmed a third death.

“Wyoming Highway Patrol Troopers and other first responders have confirmed one additional fatality as they work to investigate and clear the tragic Green River Tunnel crash that occurred at mm. 90.2 on Interstate 80 Friday,” a press release from WYDOT states.

Wyoming Highway Patrol has reportedly cleared around half of the vehicles involved in the tunnel fire. Officials said they have reached close to the center of the tunnel, which extends roughly a quarter-mile.

Investigators have determined that more than two dozen vehicles may have been involved 10 passenger vehicles and 16 commercial vehicles. Wyoming officials say they had removed four passenger vehicles and nine commercial vehicles from the crash site Saturday night, officials said.

Six commercial vehicles and two passenger vehicles were reportedly completely destroyed in the event.

WYDOT is currently planning to direct westbound traffic “head-to-head” into the eastbound tunnel by Wednesday. There are no immediate concerns that the tunnel could collapse.

“Thank you to the community of Green River for your support in keeping traffic moving during this thorough and complicated investigation,” said WYDOT District Engineer John Eddins. “We know that the detoured traffic was very impactful to your community this weekend, and we will continue to work to minimize impacts.”

Wyoming authorities are reportedly working with the National Transportation Safety Board on parallel crash investigations.

The Associated Press contributed to this report.