VANCOUVER -- North Shore Rescue is raising serious safety concerns after a slackline was set up on Mount Strachan, in the Cypress Mountain Resort area, where rescue helicopters and other aircraft are frequently flown.

A photo sent to NSR Thursday shows a person traversing the line high above a valley between two peaks.

“We were just notified that it appears someone has set up a slack line on Strachan. This is extremely dangerous and could kill our members flying in the area,” North Shore Rescue said in a Facebook post.

Slacklining, also called highlining, involves walking across a narrow stretch of suspended webbing that is just a few inches wide.

North Shore Rescue was doing helicopter training closer to Mount Seymour on Thursday, which included flying with members suspended from a longline.

Despite being in a different area, the photo was alarming to Jarrett Lunn, chief pilot for Talon Helicopters. Lunn said a line like that is hard to detect from the air and the pilots had no notification it was there.

“You can quickly think of what a worst case scenario would be,” Lunn told CTV News Vancouver on Friday. “When we’re on a rescue call, we typically work low level to the ground.”

“A slackline like that could very well take an aircraft down,” he added.

He says the area where the line is set up could be used by SAR aircraft, a police helicopter, or other agencies doing work, like BC Hydro.

Talon’s operations manager, Kelsey Wheeler, flew by the area Friday morning and saw the line is still there, though some tension had been let out. There were tents set up nearby.

“It was really hard to see,” Wheeler said, noting that if he hadn’t been looking for it Friday, he may not have been able to spot it.

“On a beautiful day, it’s easier to see, but all it would take is an overcast, grey day … and that line would be extremely dangerous.”

Wheeler and Lunn say they are hopeful this incident will lead to better communication between slackliners and the aviation community in the future.

“We understand people have the right to recreate and do things, it’s just about doing it responsibly so we can have information,” Wheeler said.

NSR says steps are being taken Friday to have the line removed.