Published: Sep 01, 2010 4:55 PM EDT
Updated: Sep 01, 2010 1:55 PM EDT

SISSETON, S.D. (AP) - Authorities say an 18-year-old South Dakota high school student stockpiled weapons and wrote about wanting to blow up his school, target individuals he hated, rape women and "become the world's most infamous sociopath."

Joseph Thomas Hansen of Claire City was arrested Aug. 23 after police received a tip from the daughter of one of Hansen's co-workers at a daycare center and searched his home. He is charged with selling, transporting or possessing an explosive device and possessing substances with the intent to make a destructive device.

Investigators say Hansen allegedly told a co-worker that the first day back from summer vacation at Sisseton High School would be a short one.

An affidavit says that in addition to Hansen's writings, police found drawings of swastikas and guides on making explosives in his room.