ROCKY MOUNTAIN NATIONAL PARK, Colo. (AP) — Searchers hope to use a helicopter in the hunt for a missing Colorado man who told friends he planned to climb the highest summit in Rocky Mountain National Park last weekend.

Park officials said the helicopter would join the search on Longs Peak Thursday if the wind isn’t too strong.

Officials believe 25-year-old Peter Jeffris of Broomfield set out for the top of the 14,259-foot peak on Sunday. His car was found at the Longs Peak trailhead.

Ground teams have been searching more than 20 square miles around the peak but haven’t found any clues.

High winds and cold weather have hampered the effort.

Thousands of hikers reach the summit of Longs Peak every year, but some routes require technical climbing skills, especially in wintry weather.

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