Three people are dead, including the pilot, and four are missing after a plane crashed into a remote lake in northern Labrador.

The pilot, 61-year-old Gilles Morin, had 20,000 hours of flying experience, according to Jean Tremblay, the chief executive of his employer, regional airline Air Saguenay.

Morin had been flying in and out of Mistastin Lake, where the plane's wreckage was found, for at least six years, Tremblay said.

Tremblay earlier confirmed the two other deaths and said the fate of four other people aboard is unclear. He said Morin was flying with four passengers and two fishing guides on board.

The plane either crashed on landing or takeoff , he said, and was found submerged in the lake about two kilometres from shore.

The Joint Rescue Co-ordination Centre in Halifax got a call at 11:30 p.m. AT that the de Havilland DHC-2 Beaver float plane was overdue.

The seven people on board were heading from a fishing lodge at Crossroads Lake, near the Quebec border, to a remote camp on Mistastin Lake. They were due back at Crossroads Lake by 6 p.m. AT Monday, but did not return.

A Hercules airplane was promptly put in the air and spotted the wreckage at 5 a.m. on Tuesday.

Two military helicopters, and a second plane chartered by the fishing lodge where the travellers were expected, are searching for possible survivors.

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

An Armed Forces spokesperson said it's too early to make assumptions about their fate.

Maj. Mark Gough said the helicopters — a CH-149 Cormorant and a CH-146 Griffon — would search the area until nightfall, at which point efforts would be handed over to the RCMP as a missing persons case, "per our normal procedures for these types of unfortunate incidents."

CBC News and Radio-Canada had previously reported there were four deaths, based on information from Tremblay. He later said that was the information he had at the time, but it has since changed to three dead and four missing.

Other crashes

The cause of the crash is unknown, and officials with the Transportation Safety Board have been called in to investigate.

All DHC-2 Beaver aircraft were built between 1947 and 1967, but it's not clear how old this plane was.

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

(CBC)

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

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

Tremblay said it's not a common part of flying, but an unfortunate reality that comes with the industry.

"It's always sad news when a crash happens."

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