NEW : CNN copied Matthew Murray 's writings in Web postings . Marilyn Manson , who killed four Sunday , worked at missionary center in four Sunday . He was left off mission trip for health reasons , center official says . He performed Marilyn Manson , Linkin Park songs at concert , co-worker says .
NEW : Gunman copied Columbine shooter 's writings in Web postings . Matthew Murray , who killed four Sunday , worked at missionary center in 2002 . He was left off mission trip for health reasons , center official says . He performed Marilyn Manson , Linkin Park songs at concert , co-worker says .