The two were separated from a pair of fellow hikers and missed a turn on a trail because of low visibility and unknowingly entered an avalanche area known as “the Lip,” triggering the avalanche that carried them to the bottom of Tuckerman Ravine, said U.S. Forest Service spokeswoman Colleen Mainville.

Mainville said the avalanche occurred at about 5:30 p.m. Saturday and the call for help came in just after 8 p.m.

Mainville said the injured and disoriented hikers climbed about 200 feet before they were met by rescuers. They were able to hike down with assistance to shelters on the mountain and were transported by a U.S. Forest Service snow cat to awaiting ambulances at about 2 a.m. Sunday.

Mainville said she doesn’t know whether they were admitted to the hospital, but she said they were treated on the mountain for bumps and bruises and one appeared to have a fractured arm. White Mountain National Forest officials are not releasing the hikers’ names.

“They were very, very lucky,” Mainville said Sunday, describing it as a very difficult and dangerous rescue mission.

At least three hikers have been killed in Tuckerman Ravine — a popular, but challenging 4.2-mile trail where large ice cliffs form in the fall and winter — since the start of 2012.

In September, a 25-year-old Canadian hiker died after he slipped and fell 150 feet while descending the trail.

In April 2012, a 67-year-old Boston man lost his footing and fell hundreds of feet into a crevasse while hiking with his son. His body wasn’t recovered until a month later. Another Massachusetts hiker died after falling 800 feet there in January 2012.

The Mount Washington Avalanche Center had reported in its avalanche advisory posted on its website Saturday morning that there was a considerable avalanche danger in “the Lip” area of the ravine, noting that human triggered avalanches “are likely.” It warned hikers that “safe travel in avalanche terrain requires training and experience.”

Sunday’s advisory said that there was a moderate and low avalanche danger in Tuckerman Ravine and that human triggered avalanches were possible.

Mainville said a half dozen organizations participated in the overnight rescue, including White Mountain National Forest snow rangers and volunteers from the International Mountain Climbing School, the Mountain Rescue Service of North Conway, Appalachian Mountain Club, Harvard Mountaineering Club and Androscoggin Valley Search and Rescue.