A search for a hiker missing in Glacier National Park since Saturday has been hampered by a lack of strong clues as to his whereabouts, although park officials say partial boot prints found might belong to the man.

The boot tracks were spotted Tuesday as the search for Jakson Kreiser, 19, expanded. One of the 12 search teams that included certified trackers with the North Valley Search and Rescue Team and a park employee identified partial tracks that match the sole pattern of boots believed to be worn by Mr. Kreiser, a Michigan man working this summer for Glacier Park, Inc. at Lake McDonald Lodge.

The tracks were located near Mary Baker Lake in the Floral Park area of Glacier. This area was previously identified and has been part of the search area.

Park officials also received a call from a hiker who was on the Hidden Lake Trail on Saturday, July 28. The hiker provided credible information, combined with other information gathered, that helps establish timing and location of Mr. Kreiser on Saturday morning.

“The clues identified yesterday are valuable in helping narrow our focus for the search efforts, and they help to identify the areas of highest probability of finding Mr. Kreiser,” said Scott Emmerich, the incident commander for the search.

The U.S. Border Patrol also has trained trackers, as well as specialized canine search teams, assisting with the incident.

The park is also using forward looking infrared technology. This technology, available through the Flathead County Sheriff's Office, uses thermal imaging cameras that detect heat sources. It is being used in early morning operations before the rocks and vegetation warm.

Ground and aerial searches have been conducted since Sunday, July 29, with several crews staying overnight in the backcountry.

The search area is focused in the area between Hidden Lake and Avalanche Lake. Mr. Kreiser’s vehicle was located in the Logan Pass Visitor Center parking lot and it is believed that he was attempting a day hike from Logan Pass to Avalanche Lake.

"His intended route is in some treacherous country filled with rock cliffs, water falls, wet and slippery rocks and boulders, and dense vegetation," the park said. "The descent is more than 4,000 feet in steep conditions."

Mr. Kreiser is believed to be wearing a yellow or gold Columbia sweatshirt, long khaki pants, and Rocky brand hiking boots, size 12. He also was thought to have a grey/yellow daypack with a 2-liter water bladder, a large sheath knife, and possibly a hiking pole.

If you think you've seen him, you're asked to call park officials at 406-888-7800, option 6.