The search for a missing hiker with dementia who disappeared without a trace from Cypress Provincial Park was suspended late Saturday night.

Debbie Blair, 65, was out hiking with a seniors group Thursday but somehow became separated from her hiking companions. She was last seen around the Donut Rock Trial junction.

North Shore Rescue called the ground and air search “exhaustive,” adding that crews scoured all areas that could be safely accessed without any sign of Blair.

Fifty search and rescue volunteers were deployed, as well as search dogs and multiple helicopters equipped with Forward-Looking-Infrared (FLIR) scanners.

Mike Danks of North Shore Rescue describes the terrain in the area as "very challenging."

"This has been a really frustrating search," he told media on Sunday. “We had very little to go on, we were in the area very quickly after she was reported missing, and unfortunately we did not have any luck whatsoever locating her.”

Blair is an experienced hiker, but she was only wearing a t-shirt and not prepared for chilly overnight weather. She is also hard of hearing.

While it was sunny when she went missing, the temperature overnight hovered not far above freezing.

Police say the search will remain suspended pending new information, and the missing person investigation will remain open.

Blair's family from Calgary will be coming from Calgary to meet with West Vancouver Police.

"Obviously it's a bit of difficult news [for them] to hear that the search is being suspended," said Const. Jeff Palmer. “But the [family] expressed that they do understand, and they are eager to meet with investigators.”

Blair is described as white, 5-4 feet, and roughly 130 pounds with short brown-grey hair. She was last seen wearing blue and white runners, white cotton pants, a light cotton shirt and a blue baseball hat.

West Vancouver Police are requesting anyone who believes they saw Blair at any time since Sept. 29 to call 604-925-7300.