They found fertilizer in one of his vehicles... if he wasn’t using it for his cactuses or a grow house but was using it for a bomb plan, medicine can’t explain that sort of planning... wonder if anything else was found to indicate he had other than agricultural plans for it.
People who commit mass murder always do it for a reason. The reason may be completely unreasonable but they usually broadcast the reason.
“They found fertilizer in one of his vehicles...”
And explosives at one of his houses. The way the Sheriff described it as “explosives and electronics” sounds like he is saying bomb making material. Seems like he was planning something on an even larger scale but for some reason settled or was rushed to this instead.