NEWPORT BEACH, Calif. (AP) — A university professor who wrote emails outlining a graphic plan to attack a California high school had been searching for information online about guns and fertilizer used in bombs in the months before he was arrested on arson charges, a prosecutor said Wednesday.

University of California, Irvine pharmaceutical sciences professor Rainer Reinscheid conducted as many as 60 such Internet searches on his home computer since March, after his teenage son committed suicide, Orange County deputy district attorney Andrew Katz told reporters after a brief hearing in the case.