A doctor is facing federal charges after falsely reporting in May that a pair of climbers he had joined in a makeshift expedition on Denali, the tallest mountain in North America, had fallen ill and needed a high-risk helicopter rescue, prosecutors said.

They said in a complaint that the doctor, Dr. Jason Lance, a radiology specialist from Mountain Green, Utah, was actually seeking an evacuation for himself after another climber, Adam Rawski of British Columbia, was evacuated following a 1,000-foot fall down the mountain.

Denali, in south-central Alaska, is the third tallest of the seven summits, the highest mountains on each continent. The National Park Service reported an increase in dangerous behavior during this year’s climbing season, which follows a similar pattern in other wilderness areas during the coronavirus pandemic. Denali, a 20,310-foot peak formerly known as Mount McKinley, was closed to climbers in 2020.

This was the rare case that resulted in federal prosecution. Dr. Lance was charged with resisting and intentionally interfering with a government employee, violating an order of a government employee and giving a false report for the purpose of misleading a government employee, the U.S. attorney’s office for the District of Alaska said in a complaint filed on Tuesday.

Contacted after a report about the charges appeared in The Anchorage Daily News, Dr. Lance would not comment. “Thanks for reaching out,” he wrote in email. “As much as I’d like to discuss the complaint, I’ve been advised not to.”

Three days after his climb, Park Service rangers at Denali warned in a blog post that they had seen several “troubling trends” during the season, including people showing “a disturbing amount of overconfidence paired with inexperience,” and climbers attempting to summit Denali too quickly. The season runs from late April to mid-July.

A Denali guide, Colby Coombs, said that guides had to assist people who weren’t their clients more than usual this year and that he was glad Dr. Lance was facing federal charges. “I hope it sends a message because someone is going to get hurt who is a rescuer and that would be a huge travesty,” Mr. Coombs said.

Few pilots can navigate a helicopter rescue above 17,000 feet and such short-haul operations put the pilot and rescuer in danger. The Park Service did send a helicopter for the group, but it turned around when guides lower on the mountain said the three climbers were making their way down on their own.

Mr. Coombs, who has climbed Denali 37 times and is the co-founder of the Alaska Mountaineering School, was not on the mountain when Dr. Lance attempted the summit, but he said details in the complaint suggested the doctor should not have been climbing without a guide.

One red flag was that Dr. Lance and Mr. Rawski were not registered as climbing partners, did not know each other well and had decided to work together shortly before the summit attempt, Mr. Coombs said. Another was that the pair either did not have rope, or chose not to use it, at crucial moments in the climb, he said.

On May 24, the two attempted the summit and Mr. Rawski showed signs of altitude sickness between 18,600 and 19,200 feet. Dr. Lance left Mr. Rawski with two other climbers they met along the way. That pair abandoned their own summit attempt to aid Mr. Rawski. Dr. Lance continued up the mountain, the complaint said.

Ultimately, he abandoned his solo climb and reunited with the other three as they approached Denali Pass, a key marker on the route. Disaster struck there when Mr. Rawski tumbled down a 1,000-foot length of the slope known as the Autobahn.

Several climbers, including Dr. Lance, reported the fall. Mr. Rawski, who could not be reached for comment, was rescued and evacuated by helicopter.

Dr. Lance then used a satellite communication device to text for assistance for the remaining three climbers, claiming they were stuck without equipment. The Park Service advised him to descend.

Nearly two hours after that first request, Dr. Lance again texted to ask for evacuation, this time adding that the two people he was climbing with were sick with shock and “early hypothermia.”

The two other climbers later told investigators they had never experienced shock or hypothermia during the climb and had spent hours trying to convince Dr. Lance to rope up with them and descend the mountain after Mr. Rawski fell. They said Dr. Lance insisted the group stay put and told them the Park Service was obligated to rescue them because climbers pay a fee to access the mountain.

The day after the failed summit attempt, Officer Chris Erickson, a Denali mountaineering ranger, spoke to Dr. Lance at his camp tent at 14,200 feet.

According to the complaint, Officer Erickson twice asked Dr. Lance for Mr. Rawski’s satellite communication device, which the doctor had taken when the pair initially split up.

Dr. Lance said no twice, rustled through his belongings, then told the ranger his privacy was being violated and zipped up his tent. From outside the tent, the ranger told Dr. Lance he could face legal consequences for deleting any messages. He eventually turned the device over.

“Dr. Lance responded with statements about his privacy and stated that N.P.S. should have rescued him (Dr. Lance) the previous night,” the complaint said.