A Montana Rail Link (MRL) freight train pulling “several hazmat cars” crashed into the Yellowstone River on Saturday, after the bridge it was crossing collapsed. Local officials said they were “unsure” if the collapse or derailment occurred first. 

No injuries have been reported from the incident.

The cars which ended up in the famous river (which flows into and gives its name to Yellowstone National Park) contained asphalt and molten sulfur, according to MRL. Neither of the substances is believed to have entered the water, according to the company. 

The substances would solidify if they came into contact with the cool water and would therefore cause significant environmental damage. 

Another dangerous material, sodium hydrosulfide, was carried in several of the train cars which did not end up in the river and, according to MRL, have not escaped the cars. 

MRL’s spokesperson Andy Garland told Rail Technology: “The car remains safely out of the water and there has been no release involving this material. We continue to closely monitor all releases involving molten sulfur and asphalt and mitigating any impacts to the site and surrounding area.”

The incident happened at 6:45am, roughly 60km from the nearest city Billings. 

MRL is working with local law enforcement and the Environmental Protection Agency (EPA) to clean up the effects of the crash and deal with any consequences.

“Montana Rail Link remains committed to addressing any potential impacts to the area as a result of this incident,” Garland added.

Unified Command, consisting of the EPA, Stillwater County, MRL and the Montana Department of Environmental Quality said the cleanup is progressing but “a lot of work remains”.

An official from Unified Command explained: “Ten cars are in the river, six contain asphalt, three contain molten sulfur and one contains scrap metal. The condition of these cars, including two that are submerged is a key unknown in the plan to remove them from the water.

“A dive team has arrived on the scene to gather more information about the situation below the surface. Contractors and a large crane have been brought onsite to stabilise and remove these cars from the river.

Montana governor Gianforte visited the site on Monday and along with Montana’s national representatives, is monitoring the situation.

The Yellowstone County Sheriff’s Office in Billings also confirmed on social media that “Water treatment plants, irrigation districts and industrial companies are taking appropriate precautions”.

The Federal Railroad Administration has initiated an investigation into the crash and its causes.