Man charged in pregnant wife's death plans insanity defense

A Pennsylvania man accused of killing his pregnant wife with a sword last year plans to use an insanity defense.

Lawyers for 32-year-old John Ziegler III stated their intent in court papers filed earlier this month.

Ziegler is charged with homicide in the deaths of 25-year-old Diana Ziegler and her unborn child in January 2017 in Jackson Township. Authorities say the victim was six months pregnant.

Officials said the defendant told investigators that he believed he was saving humanity from a global conspiracy involving what he called "hybrid humans."

Police have testified that Ziegler told investigators his wife was the group's "queen bee" and that he needed to kill her to save the world.