Police say the helicopter, owned by Vancouver Island Helicopters, was conducting a geological survey in the area. (Vancouver Island Helicopters)

Transport Canada will lead an investigation into a helicopter crash that killed three men in northern B.C. on Sunday.

Police say the helicopter, operated by Vancouver Island Helicopters, was carrying a pilot and two passengers when it went down near Stewart, about 160 kilometres north of Prince Rupert on B.C.'s northern coast.

Police say the helicopter was under contract to a mining company, and the two passengers on board were conducting a geological survey in the area.

It it not yet clear why the chopper went down, but Bill Yearwood with the Transportation Safety Board of Canada — a federal agency that investigates transportation accidents — said there were high winds at the time.

"It was quite windy and the terrain being rough, it's been reported there were a lot of downdrafts in the area at the time, but that is just hearsay at this time," Yearwood said.

RCMP Cpl. Dan Moskaluk said the helicopter crashed in a very remote location.

56.055 -129.618889The approximate location of the helicopter crash

"It was strictly a fly-in area only," he said.

"There's no road access to the site. [Investigators] were able, though, to get to the site to do the initial survey and then ... it is my understanding that the lead investigating agency will be returning to examine the site and look at what evidence they can recover to hopefully determine what caused the crash."

Moskaluk said a crew with Vancouver Island Helicopters helped transport investigators to the site.

"[Investigators] were able to photograph the scene and unfortunately confirm again that the three souls on board did perish in the crash."

The names of the victims are not being released until their families have been notified.

In a written statement released Monday, Vancouver Island Helicopters offered "sincere condolences to the families and friends of the accident victims."

The company extended "heartfelt sympathies to those directly impacted by this tragedy."

The statement said family members of the victims have been contacted and are being offered counselling and support.

The statement also referred to the remote location of the crash site, saying "weather conditions in the area are currently hampering the ongoing investigation efforts."

The statement says the company is working and co-operating with investigators and awaiting the results of the investigation.