John Earnest is accused in a shooting at Congregation Chabad synagogue in Poway, California.
CNN  — 

The Christchurch mosques shooting may have inspired the 19-year-old suspect behind the hate-motivated shooting at a synagogue near San Diego, according to a manifesto posted online under the same name as the California suspect.

John Earnest is accused of one count of murder and three counts of attempted murder after a shooting at Congregation Chabad synagogue in Poway, California, left one person dead and three others wounded on Saturday. Fifty people were killed in the New Zealand mosque attacks on March 15.

Seventy-three minutes before the Poway attack, someone identifying himself as John Earnest posted a link to a hate-speech-filled manifesto hyperlinked on 8chan, an anonymous message board that often features hate speech and extremist posts.

In a Twitter post, 8chan says it took down the post nine minutes after it went online.

CNN has reached out to 8chan to see if it alerted law enforcement about the threat.

The FBI said in a statement it was not able to determine the author of the post.

In the post on 8chan, the individual identifying themselves as Earnest wrote an open letter, which is filled with anti-Semitic and white nationalist sentiment. The author talks about planning the attack and cites the New Zealand attack in several instances, saying it “was a catalyst” and had “inspired” him. Robert Bowers, the suspect in the Tree of Life Synagogue shooting in Pittsburgh, is also mentioned as a direct inspiration.

The open letter is structured in a question-and-answer format in which the person identifying themselves as Earnest answers general questions about his character, political affiliation and motivation for carrying out an attack.

In the 8chan post, the individual identifying themselves as Earnest says he’s “only been lurking” on the site for a year and a half, before linking to a Facebook page saying “a livestream will begin shortly.” The New Zealand attack was livestreamed on Facebook.

This time, no live video was found on the Facebook page linked on the 8chan post, according to archived web pages.

A Facebook spokesperson told CNN the account was disabled for “violating our authenticity policy,” but refused to identify what part of that policy the account had broken. They went on to say the company has not found any video associated to the account linked in the 8chan post.

Four minutes after the original post, an 8chan user responded to it by praising the poster and encouraging him to “get a high score,” meaning to kill a large number of people.

The individual identifying themselves as Earnest used the document dumping sites Pastebin and Mediafire to post their manifestos.

Facebook took down the Facebook page linked in the 8chan post around 8 p.m., several hours after the shooting.

CNN’s Artemis Moshtaghian contributed to this report.