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 sent 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.