Glacier National Park. (Glacier National Park Service)

This post has been updated.

The search for two hikers from the mid-Atlantic region who have gone missing in the Montana wilderness is expected to continue on Monday.

Neal Peckens of northern Virginia and Jason Hiser of Richmond, Va., had been hiking in Glacier National Park last week, the National Park Service said in a news release. Their families reported them missing Friday night, after the men, both 32 years old, missed their flights home.

The men’s car was found late Friday, and a formal search for them began on Saturday.

Peckens and Hiser are believed to still be in the park, where they had a permit to camp in the backcountry. Park officials have a general idea of the area where the men planned to camp and hike, on the east side of the park.

About 50 people searched for the two men on Sunday. They found a recently used fire ring and tracks believed to belong to Peckens and Hiser.

The area where the fire ring and tracks were found was described by officials as “some very dense, steep and treacherous terrain.”

Some members of the search team were expected to stay out in the backcountry Sunday night and others are expected to resume the search Monday morning.

Officials reported that the biggest danger to the men — and the greatest hindrance to the ongoing search — is the wintery weather that has already hit the park.

Eighteen inches of snow on trails, snow drifts, limited visibility and extreme winds have been reported. It is unknown if the men were prepared for these conditions.

Officials believe the men may have lost the trail because parts of it were covered with snow.

Both men are veterinarians and both originally are from western Maryland. Family members say the men are experienced hikers.