Tetsuya Yamagami indicated he planned to kill former Prime Minister Shinzo Abe in an anonymous letter sent to a freelance writer who has also criticized the Unification Church, investigative sources said.

Nara prefectural police seized the letter on July 17 despite the objections of the writer, who is based in Matsue, the capital of Shimane Prefecture, sources said.

The writer told investigators he has never met Yamagami, and that he noticed the letter had been sent to his home on July 13.

Abe was shot and killed in Nara on July 8. Police suspect Yamagami, 41, mailed the letter from Okayama the day before the shooting.

The murder suspect is believed to be an avid reader of the writer’s blog, which contained posts critical of the Unification Church, known formally as the Family Federation for World Peace and Unification.

“I have spent (time) trying to obtain guns,” the first part of the letter says, according to the sources. “My connection with the Unification Church dates back about 30 years.”

He also wrote that his mother had given more than 100 million yen ($719,000) to the religious group after she joined it, and those donations led to the destruction and bankruptcy of his family, the sources said.

“My teen years passed with these developments,” the letter says. “It is not an exaggeration to say that what I experienced in those years distorted my entire life.”

The letter’s envelope also contained a “statement of mutual agreement” between the Unification Church and his family over donations, the sources said. The statement showed his handwritten name and address.

According to the sources, Yamagami referred to Abe, 67, in the latter part of the letter, saying he “is not my enemy, originally.”

The letter describes Abe as “just one of the Unification Church’s sympathizers who wields the most influence in the real world.”

Yamagami contemplated killing the Unification Church’s founding family for some time but realized that it would be impossible, according to the letter.

The letter concludes, “I can no longer afford to think about the political implications and consequences that Abe’s death would bring.”

The A-4 size printed letter did not mention who was the sender.

Yamagami told investigators that he brought a concealed gun to a venue in Okayama where Abe gave a speech for a candidate running in the Upper House election on the night of July 7, according to the sources.

But he did not attack the veteran politician that day. Instead, he waited for Abe’s appearance in Nara the following day, the sources said.

Police believe the letter was mailed before Abe gave the speech at the Okayama venue.

The writer in Matsue told The Asahi Shimbun that he had “declined” police’s request to hand over the letter. But police seized it on the evening of July 17.