ANCHORAGE, Alaska — A teenager has died after triggering an avalanche, the fourth person killed in snow slides in Alaska this month.

Alaska State Troopers said the body of 16-year-old Tucker Challan of Soldotna was recovered from the avalanche Sunday by the Alaska Mountain Rescue Group.

Troopers said a group of snowmachiners were riding Saturday on the backside of Seattle Ridge in Turnagain Pass, a popular winter recreation area about 60 miles southeast of Anchorage.

“Witnesses stated that a juvenile male triggered an avalanche and died after being buried,” troopers said in a statement.

Challan was buried about 10-feet deep in the slide that measured about 500 feet wide, said Wendy Wagner, director of the Chugach National Forest Avalanche Center.

Conditions are worrisome because a weak layer is located about 3 feet beneath the snow surface, with newer snow falling on top of the weak layer.

Challan rode over a weak layer of snow that was buried under newer snow, about mid-slope, Wagner said.

When the slide happened, the center’s staff was conducting an avalanche awareness day in a parking lot on the other side of Seattle Ridge, she said.

“These types of avalanches, they can be triggered when you’re on this slope. They can be triggered when you’re on the bottom of the slope and even the side or the top of a slope, because all you have to do is break that weak layer, and then that weak layer shoots out like dominoes and breaks into the slopes,” she said.

The weak layer can be broken on a flat track, but that wouldn’t cause an avalanche because there is no slope for the snow to come down.

“When we have avalanche conditions like this, as avalanche professionals, we recommend people just stay on slopes that aren’t steep enough to slide, and then they don’t have to worry about triggering an avalanche, and sadly, this person was not in that scenario,” Wagner said. “They were on the edge of the slope and ended up being caught.”

The avalanche center has been warning people of this weak layer for weeks, and there were similar conditions on March 4, when three heli-skiers were killed. That accident happened when they were caught in an avalanche near Girdwood, about 40 miles south of Anchorage.

“It’s still unsafe,” Wagner said Monday. “We are still recommending that people stick to the lower angle slopes because this is not something we want to mess with.”