The gunman who police say open fired on a Southern California church congregation, due to his political hatred for Taiwan, has labelled himself the "destroying angel."
David Cho, 68, sent a seven-volume diary to a newspaper before his attack, a paper has confirmed.
According to police, Cho killed church congregant John Cheng in the shooting at Irvine Taiwanese Presbyterian Church in the community of Laguna Woods on Sunday.
Cheng was named a hero after allowing other individuals to subdue Cho, hogtie his legs with an extension cord, and take away his weapon.
Four other Asian men were injured as well as an 86-year-old Asian woman.
Before Sunday, Cho spent $16.10 (£12.95) to mail a seven thick photocopied volumes of handwritten Chinese text and a flash drive to the World Journal office in the Los Angeles suburb of Monterey Park. This is according to photos published in the Chinese-language paper.
The paper was entitled "Diary of an Angel Destroying Independence" referencing to the Taiwan's self-government. The diary pages were received on Monday, just one day after Cho carried out the shooting.
Cho, who has not entered a plea and remains in jail could face life in prison or the death penalty if convicted of murder and attempted murder.
He has no bail in Orange County pending a 10th June arraignment.