Four Americans, two men from Newfoundland and Labrador and one Quebecer are dead or missing after a plane crashed into a remote lake in northern Labrador.

Police confirmed where all seven men were from on Wednesday afternoon, hours after they changed the rescue mission for four of the passengers into a recovery mission.

The Air Saguenay float plane was found in the waters of Mistastin Lake, and an underwater recovery team will head down to the wreckage to search for bodies, a spokesperson for the RCMP said.

Police say it's not known if anyone's remains are inside the plane.

Mistastin Lake is about 100 kilometres west of the Innu community of Natuashish on Labrador's northern coast.

Three of the people aboard the plane — including pilot Gilles Morin, 61 — were confirmed dead hours after the wreckage was found. Four are still missing.

A search found the de Havilland DHC-2 Beaver float plane submerged about two kilometres from shore in Mistastin Lake.

The plane crashed into Mistastin Lake either on takeoff or landing, according to the head of the airline. (Michael Zanetti)

Air Saguenay said Morin was flying with two fishing guides from N.L. and four other passengers. They were were heading from a fishing lodge on Crossroads Lake near the Quebec border to a camp on Mistastin Lake.

The party was due back at Crossroads Lake early on Monday evening, but did not arrive. A Hercules aircraft spotted the wreckage early Tuesday morning.

The RCMP have now taken over the investigation into the crash.

Airline president: Beaver float plane 'safe'

It's the third fatal crash of a Beaver plane belonging to Air Saguenay since 2010.

"Everybody is in shock, because this is a friend of everybody in the company," Tremblay said Tuesday.

One crashed into a mountainside near Lake Péribonka, Que., in bad weather on July 16, 2010. Four of the six people aboard were killed.

In 2015, another crashed into a remote wooded area near Les Bergeronnes, Que., killing all six aboard.

But Tremblay insists it's a "safe plane."

"The Beaver [has operated] since the 50s and is still in operation," he told CBC on Wednesday.

It's not known how old the aircraft that crashed was. Beaver aircraft were in production between 1947 and 1967.

(CBC)

In the previous two crashes, "we can say it was human error ... it's not an issue with Beaver," Tremblay said, citing the Transportation Safety Board.

Tremblay said he doesn't know if the people onboard were wearing personal flotation devices (PFDs), and even if they were, he said, "its hard to see if [PFDs] would have helped or not."

Safety Board investigators will examine crash

Tremblay said the crash likely happened during takeoff or landing, and the cause is not known yet.

He added Morin had been flying in and out of Mistastin Lake for at least six years.

Tremblay said employees are coming together in the wake of the "horrible accident."

"Air Saguenay, I can say it's a small family. We are together … we will face it, we will go through this matter," he said.

Two military helicopters and a private plane chartered by the fishing lodge assisted Tuesday with the search.

Investigators with the Transportation Safety Board (TSB) will be travelling to the area to help determine what happened, but not until the aircraft is recovered, according to TSB spokesperson Alex Fournier.

"The investigators will look at the aircraft, document what they see, take pictures; they may decide to take a part of the aircraft back to our lab here in Ottawa," he said.

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