CONCORD, N.H.—New Hampshire prosecutors have charged a Vermont man with fatally stabbing a 70-year-old woman at a Hampton Inn in Littleton, N.H., in what appears to be a random attack.

Rodney Hill of West Danville, Vt., was being arraigned Tuesday on second-degree murder charges in the death of Catherine "Kitty" Houghton of Novato, Calif., a career commercial counselor with the U.S. Foreign Service who served as a trustee at a private school near where she was killed.

Houghton is an alumnus and member of the board of trustees at the White Mountain School in Bethlehem, where she delivered the commencement address in 2011. She has a pilot's license and volunteered her services for Angelflight—which provides transportation to indigents in medical need, according to a tribute on the school's website.

Senior Assistant Attorney General Susan Morrell said Littleton police were called to the Hampton Inn just before 9 p.m. Monday. They found Houghton with multiple stab wounds to the neck and torso. Police say they encountered Hill outside the hotel and took him into custody.

Houghton died later at Littleton Regional Hospital. An autopsy was scheduled for Tuesday.

Prosecutors have made no mention of a motive in the killing. WMUR-TV reports ( http://bit.ly/XIjlAU) Morrell said Houghton and Hill did not know one another and the killing appears to be random. Hill is being held without bond.

Houghton obtained her master's and doctorate degrees from Stanford University, according to the White Mountain School website, and spent most of her career as a commercial counselor for the business division of the U.S. Foreign Service.