Several Killed in Multi-Vehicle Pileup in Wyoming Tunnel That Ignited Blaze

Several people were killed and others are hospitalized after a multi-vehicle crash in Wyoming caused a fire in a highway tunnel.

According to the Wyoming Highway Patrol, troopers were called to the scene of a crash at Green River Tunnel, located on the state’s highway I-80 in about 160 miles northeast of Salt Lake City, Utah just after 11:30 a.m. on Friday, Feb. 14.

In photos shared by the Wyoming Department of Transportation (WYDOT), thick, black smoke could be seen billowing out from the rural tunnel as multiple semi-trucks appeared smashed together. The cause of the fire was not immediately known.

The highway was closed in both directions, and the Sweetwater County Sheriff’s Office added in a Facebook post that the fire remained an “explosion threat.”

The names and total number of people who died were not made immediately available, though The Associated Press reported at least two people were killed.

According to local outlet Cowboy State Daily, Wyoming Highway Patrol troopers also said that tires on vehicles at the scene were exploding from the heat generated from the fire.

“There are fatalities, but I don’t know any details on those at this time,” John Eddins, district engineer for WYDOT District 3, told Cowboy State on Friday. “I don’t know the cause of the accident, but it involved several semis and a couple of passenger vehicles.”

The Memorial Hospital of Sweetwater County wrote in a statement that it was providing care for the “mass casualty event.”

“As a community please be advised that we are working to provide care and take care of those that are involved. If you and your immediate family are not involved, please refrain from visiting the hospital unless it is an emergency,” the hospital wrote on Facebook.

Steve Core, the communications administrator for the City of Green River, told local outlet SweetwaterNOW that firefighters were pulled because concrete began falling from the tunnel roof.

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Stephanie Harsha, a public relations specialist for WYDOT District 3, also told SweetwaterNOW that severe structural damage has been reported inside the tunnel, but that structure has not yet collapsed.

Mower added to Cowboy State that WYDOT personnel were using Gov. Mark Gordon’s plane and had started heading to the scene by 2 p.m. local time. He also said that the Wyoming Division of Criminal Investigation, Wyoming Highway Patrol, WYDOT and the sheriff’s office are all investigating.

“Basically, we treat it as a giant crime scene,” Mower told the outlet.

“Law enforcement and fire crews are working in the area and drivers are asked to stay clear of the area,” WYDOT District 3 wrote on Facebook at 2:15 p.m. local time, adding that authorities are unsure when the road might reopen.

The Sweetwater County Sheriff’s Office did not immediately respond to PEOPLE’s request for comment.