MONTREAL -- Five people are missing and one is dead after a group of snowmobilers plunged through the ice near Quebec's Lac Saint-Jean.

Late Wednesday, provincial police said they found two snowmobiles underwater close to where the snowmobilers had gone missing, near the mouth of La Grande Décharge on Lac Saint-Jean.

It happened at 7:30 p.m. Tuesday near Saint-Henri-de-Taillon, about 500 kilometres north of Montreal.

Eight tourists from France and their tour guide were part of the group, Sûreté du Québec (SQ) spokesperson Hugues Beaulieu told CTV News.

He said three members of the group managed to help each other out of the water and rushed for help. They were treated for hypothermia.

Their tour guide, who police identified as 42-year-old Benoît L'Espérance, was rescued by firefighters, but later died in hospital.

A search Wednesday morning involved provincial police on snowmobiles, local firefighters and Canadian Armed Forces personnel. Divers arrived onsite at 8 a.m. to continue looking for the missing five members of the group.

Meanwhile, an SQ helicopter crashed while combing the eastern side of the lake. The pilot, who was the only person on board, was rescued by colleagues and taken to hospital for treatment. He is expected to survive.

SQ officers say they are searching the shoreline in case some of the missing made it to shore. They are also assisting the province's coroner in an investigation.

Beaulieu says the area where the incident occurred isn’t on a marked trail, where snowmobilers are usually required to circulate.

He adds provincial police do not recommend snowmobilers go off trail.

Andrée Laforest, minister responsible for the Saguenay-Lac-Saint-Jean region, says the Quebec government is in contact with authorities in France and the families are being contacted.

"There are questions people are asking, such as, 'did they get lost?'" she said Wednesday in Quebec City. "That will be part of the investigation."

In the hours following the incident, authorities stressed the dangers of straying off marked snowmobile trails.

Gaëtan Gagné, president of the Lac-Saint-Jean snowmobile club, notes the area where the incident occurred, known as the Grande Décharge, is known to be extremely dangerous.

"Enthusiasts in the area, they know it well," he said in a phone interview. "They know you shouldn't go near the Grande Décharge because there's a dam lower down, so the water isn't calm. It almost never freezes."

Gagné adds the snowmobilers must have been "at least a couple of kilometres" off the trails, which he said are well-marked and easy to follow.

France Paradis, a retired journalist and snowmobiler who lives in the area, echoed Gagné's thoughts.

He says it's unusual for guided tours to be out at 7:30 p.m., especially in an area known for open water and fast currents.

"A professional guide who knows the area well would never go there, especially at this time of the year," he said.

Laforest states it is still too early to speculate about how the group came to be where they were. She says the Quebec government is working on a new framework to regulate the province's tourist operators, which will be announced in the coming days.


SNOWMOBILE SAFETY WEEK

Laforest noted the incident occurred in the middle of International Snowmobile Safety Week. 

The Quebec Federation of Snowmobile Clubs is running a campaign to educate people about safe and responsible snowmobiling practices by riding on trails, handing out pamphlets and reminding people of the rules.

Its biggest tip: Don't veer off the trails.

"Stay on groomed trails, especially on bodies of water," said Michel Garneau, with the federation. "Trails are the only place where it's proven to be safe for people to go snowmobiling. As soon as you get off the trail, you're rolling the dice."


MINISTER PROMISES CHANGES

Laforest met officials at the SQ command post late on Wednesday, promising legal changes that could prevent this type of incident. 

A press conference had already been planned for Thursday to announce changes to the law concerning adventure sports, which includes snow mobiling, the minister said.

"We are all just overwhelmed," she said. "This is the region for snowmobiling. I just couldn't believe there was a tragedy of this magnitude."

-- with files from The Canadian Press.