It's not Blair Witch Project terrifying, but video of a bear encounter last week captured by an Abbotsford man who was mountain biking on Mount Seymour does have all the hallmarks of a scary movie.

Brad Martyn and his two friends first spotted the black bear off in the distance as they were about to descend the black diamond TNT trail for the first time.

That's when Martyn started recording on his helmet-mounted camera.

Thinking it prudent to put some space between themselves and the animal, the group hurried down the single track at a good clip.

Watch as the bear appears mere metres away after a frenetic bike ride down the mountain

A group of mountain bikers were chased by a fast moving black bear as they rode down a black diamond trail on Mount Seymour. 1:09

To their shock and surprise, the bear not only followed, it got closer.

"I look back and then all of a sudden the bear is another 30 feet closer and running at us," said Martyn.

"I don't know if he's on the trail or cutting through the bush, but we're like, this doesn't make any sense. Why is he chasing three grown men?"

The men navigated the trail for a couple of anxious minutes before finally stopping to see if they had shaken their stalker.

'This isn't normal'

Suddenly, the bear reappeared only metres away.

"That's when I kind of got a knot in my stomach," said Martyn. "Like, this isn't good, this isn't normal. [A bear] shouldn't be chasing us for that long, for over a kilometre."

Brad Martyn says the bear chased him and his two friends for over a kilometre. (submitted by Brad Martyn)

On the video, you can hear the panic rising in the men's voices as they try to figure out what to do.

They finally decide to position their bikes to try to look bigger and then start yelling and throwing rocks.

The bear reluctantly moves away but still followed the men for a short time after, albeit from a greater distance.

Martyn says he's no stranger to bear encounters having spent years mountain biking in Whistler, Squamish and the Lower Mainland. But, he says, this time he felt nervous.

"Normally they just smell you and take off," he said. "I don't know if he was curious or smelled food or maybe he was a younger bear that just wanted somebody to play with."

Martyn say next time he goes mountain biking on Seymour, he'll pack bear spray.