Denver shooting spree suspect Lyndon McLeod, who shot and killed five people on Monday night, has reportedly written and published a novel.

Most of the victims were connected to the tattoo industry. According to Daily Mail, McLeod's self-published novel tells the story of a character with his name that murders people at tattoo parlors as an act of revenge against the world.

The 47-year-old gunman was known as an extremist with psychiatric problems and had violent material on his social media. Police killed him on Monday at the end of his shooting rampage across Denver.

McLeod self-published a series of novels online from 2018 to 2020 under the pseudonym Roman McClay. One of the books features a character named "Lydon McLeod" who opens fire to a tattoo parlor in downtown Denver.

The McLeod in the book goes on a six-month killing rampage that killed 46 people who had wronged him throughout his life.

One of his stories also featured a character who murdered someone at an apartment complex, which is similar to the site of one of the shootings.

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Lyndon McLeod and Denver Shooting

Lyndon McLeod posted videos online of himself that showed living an isolated life in the mountains, living out of a storage container, as well as frequently shooting guns.

McLeod posted a photo of himself holding a long gun on an Instagram profile with a user handle @sanctionthebook, which has now been taken down, CBS Local News reported. He did several interviews and podcasts on YouTube five months ago, mainly about his book series.

The Denver shooting suspect had already come on to the radar of police and had conducted an investigation on him twice. However, they did not find a reason to charge him. Police did not also say why there was a concern.

Law enforcement sources claimed that McLeod has a history of psychiatric episodes, including being inclined to alt-right conspiracy theories online. He also shared COVID conspiracy meme that shows Facebook CEO Mark Zuckerberg and Microsoft founder Bill Gates talking about an "injectable nanoworm," New York Post reported.

The Denver Shooting Suspect as Roman McClay

Denver police Chief Paul Pazen did not confirm McLeod's pen name, which is Roman McClay. However, news outlet The Denver Post confirmed the pen name through an acquaintance of McLeod's.

McLeod's family said they were devastated by McLeod's actions while mourning the victims of his attack.

He named both Alicia Cardenas and Michael Swinyard as murder victims in his novels. Cardenas, 44, and Swinyard, 67, were both killed in the Denver shooting on Monday.

The first book reads that "killing people nourished the soul." It also stated that the "murders were like food in the belly, like wine at rest on the tongue."

The tattoo shop is also named in the suspect's novels. McLeod was seen near a Wells Fargo bank during the shooting, according to police.

McLeod's novels also stated that the bank is the target of a robbery. He described banks in his book as the "largest corporate criminal."

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This article is owned by Latin Post.

Written by: Mary Webber

WATCH: 5 Killed In Shootings: Books, Social Media Posts By Suspect Lyndon McLeod Include Rants And Fantasies - From CBS Denver