A full-scale search for an American documentary filmmaker continued Monday in Northern B.C. as concerns for his safety grow.

Warren “Andrew” Sill, a 26-year-old from Ohio, has been missing since July 5 after telling family and friends he planned to spent five days in the woods at Whiskey Creek Trail to capture spirit bears on film.

A helicopter, RCMP dog team and scores of volunteers are helping search and rescue crews in the ongoing search, but police say they are very concerned about the inexperienced hiker’s wellbeing.

“The concern is that this young man was out there and not equipped for the terrain,” said RCMP spokesperson Const. Lesley Smith. “It could be a case of him not being able to get his bearing right. In that case, being dehydrated will affect his wellbeing. He’d be disoriented if he hasn’t kept up with fluids and nutrients.

Lack of nourishment is a real risk, considering Sill was already a week overdue.

Sill’s cell phone and tent had been left in his vehicle, which was found abandoned at the entrance of the trail.

Smith said the terrain is extremely challenging and features plenty of drops and hazards, which could also play a role in the disappearance.

But searchers will continue to search for Sill until they feel they’ve exhausted all their resources and extensively covered the terrain, Smith said.

Anyone with information of Sill’s whereabouts is asked to call 911 immediately.