BERLIN — A fire swept through the mountaintop retreat built for Adolf Hitler and known as the Eagle’s Nest as emergency services struggled to tackle the blaze in snow and wind, and a man was arrested on suspicion of arson, authorities said Saturday.

Emergency services in the Berchtesgaden district, in the Bavarian Alps in Germany’s southeastern corner, were alerted to the fire by an alarm at about 9:15 p.m. Friday. Firefighters and police rushed to the scene — located at the end of a narrow road that winds up the mountain, in part through a series of tunnels — and could see the flames as they approached.

They stopped and arrested a man on a motorcycle driving the other way down the road.

Prosecutors said the 33-year-old suspect, a German citizen who has ties to the Berchtesgaden area but doesn’t currently live there, was questioned. They said he showed signs of mental illness and he was being set to a psychiatric facility, but they also would look into the possibility of a political motive in view of the building’s history. Police said there were no current indications that anyone else was involved.

Rain that turned into the season’s first significant snow, accompanied by strong wind, complicated the already difficult task of tackling the blaze and firefighters had to pull out overnight after several hours, officials said. No one was injured in the fire, and firefighters hoped to finish their work on Saturday though they weren’t able to enter the building because of a danger of falling material.

The building, known in German as the Kehlsteinhaus, is located on a cliff 1,834 meters (6,017 feet) above sea level. It is reachable by an elevator built inside the rock from the end of the mountain road, which is closed to public traffic but used during the day by buses for visitors.

It has been operated as a cafe and restaurant since 1952 and contains an exhibition on its history. The Nazi dictator himself rarely used the Kehlsteinhaus — unlike the Berghof residence, also in the Berchtesgaden area, the ruins of which were blown up in 1952.

The Obersalzberg Documentation Center, further down the mountain, is home to the area’s main historical exhibition and was unaffected by the fire.

Officials indicated that the Eagle’s Nest would be restored, though they were vague so soon after the blaze about how exactly that would be done.

“We’re not going to leave a ruin there,” Bavaria’s interior minister, Joachim Herrmann, told reporters in Berchtesgaden. But what the site will look like in the future will be a matter for discussions with local officials, historians, preservationists and others.

“I think we will be able to find a sensible solution,” Herrmann added. Bavaria’s state government owns the building.

The minister stressed that “it is important that we continue to do the work of remembrance.”