The Consulate General of Japan in Detroit said Wednesday that Matthew P. Johnson was last seen Friday, and his car was found parked at the mountain.
Johnson is from Portage and was in Japan on business. He works for Eaton Corp., and is described as an avid hiker and outdoorsman.
The consulate said searchers have used a helicopter and ground crews, but bad weather has hampered the search. A renewed search was expected today, weather permitting.
The consulate said the mountain near Tokyo is very popular in the summer, but considered “extremely dangerous” in the winter.