A snowy stretch of a northeastern Ontario highway was covered in silver and gold Wednesday, after a tractor-trailer crash left the road strewn with up to $5 million in brand new Canadian coins.

The crash occurred at approximately 4 a.m. local time Wednesday, when a fully-loaded Brinks tractor-trailer crossed the centre line on Highway 11 north of Kirkland Lake, slamming into a rock cut.

That impact triggered a series of collisions that ultimately involved another two tractor-trailers, one of which was packed with candy, and a minivan.

While the drivers of those two trucks have been treated for minor injuries and released, the minivan driver escaped unscathed.

The driver and passenger in the Brinks truck were not so lucky, however, sustaining serious, life-threatening injuries in the crash. One was taken to Bingham Memorial Hospital in Matheson and the other to the Kirkland Lake District Hospital. Both remain in hospital, with what the Ontario Provincial Police called life-threatening injuries.

Earlier Wednesday, South Porcupine community services officer Const. Marc Depatie told CTVNews.ca that police are investigating the cause of the "vehicular carnage," while Brinks employees work to clear the coins from the accident scene.

"It is rather unique in the fact that such a sizable amount of Canadian currency is strewn about a collision," Depatie said, explaining that the truck could have spilled between $3 and $5 million in uncirculated loonies and toonies.

"We are going to be using magnets and other less sophisticated means of collecting the cargo," he said, explaining that Brinks personnel are leading the retrieval efforts while police technical investigators try to piece together what happened.

In a news release, the OPP described the debris field as "massive."

Pictures from the scene show a dusting of snow on the road, which was littered with twisted metal, cardboard currency boxes and the mangled wreckages of the trucks.

Piles of loonies and toonies that had spilled from their plastic casings filled the roadway.

When asked about the prospect of curious passers-by who might hope to help themselves, Depatie said police had not had any security concerns.

"We're maintaining control of the scene, so there are none at present," he said. "And Brinks has their own personnel on site to safeguard the well-being of the cargo as well."

Police expected Highway 11 to remain closed in the accident area "for hours." Police said Highway 101 was open for east-west traffic.

In the meantime, traffic is being rerouted along Highways 655 and 144.