Randy Stair, who idolized the Columbine killers and left behind a chilling online presence that included a final video pledging death and filled with guns, was identified as the suspect who killed three co-workers at a Weis Market grocery store in Tunkhannock, Pennsylvania.

“Goodbye humans,” Stair wrote on Twitter using his fake name, Andrew Blaze, shortly before he barricaded exits and massacred three co-workers. Police said that Stair killed himself after the rampage, which occurred at a grocery store where he also worked.

Stair, 24 and from Dallas, Pennsylvania, was a YouTuber with a following, but his posts ended up being a chilling warning of what he was planning, and he filled social media with photos and videos of himself toting around guns, even kissing them, and posing for pictures in the grocery store. His Twitter profile says, “Join us and leave your life behind.” He labeled some videos “suicide tapes” in his final days.

The shooting unfolded just before 1 a.m. on June 8. Stair blocked entrances to prevent people from fleeing before committing the massacre, reported York Dispatch.

Stair had given ample warnings on social media that he was capable of mass murder. You can watch some of his disturbing videos below, which he posted under a channel he called “Ember’s Ghost Squad,” and read some of his suicide notes, but be aware that they are troubling and contain explicit language.

The Westborough High Massacre (EGS) / Goodbye

“All souls are fair game,” he says in one chilling video. His suicide notes paint the picture of a depressed and angry loner who has lost faith in humanity. He appears to have created a prolific online sort of last will and testament, providing a chilling view into the twisted mind of a killer in a social media age.

“I’m so ready to die. Two more fun nights and that’s it,” he wrote in an online journal left for the world to see. “I’ve officially accepted that Wednesday night will be the death of me. Everything around me seems to have faded away. It’s felt as if I’m the last soul alive on this planet for the last week. I see people but they feel like an illusion. I’ve never felt so distant from society… and I love it.”

Here’s what you need to know:

1. Randy Stair Left a Disturbing Final Video in Which He Revealed He Was Going to Kill People & Urged Everyone to Watch the Headlines

Stair left a disturbing and prolific online presence behind, much of it written in a pseudonym. In some of the videos, Stair waves around weapons and goes target shooting. His social media presence spans Instagram, Twitter, Facebook, and YouTube, as well as other platforms, many of which have since been deleted.

He wrote this ominous message:

He was “a loner who idolized the teenage gunmen responsible for the 1999 massacre at Columbine High School in Colorado and who found escape through the YouTube videos he created under the Andrew Blaze name,” reported the Times Tribune.

He posted a final video that indicated what he was planning. One video was even called, “Supermarket Tour June 7 – The Day Before the Shooting,” and shows him walking around a grocery store. One of his scribblings read, “These are all of the audio and video recordings pertaining to my death. All of these recordings and videos are essential for understanding what I did and how I did it.”

Randy Stair (Weis Market Shooter) – 13 Goodbye Earth Final Video June 03, 2017

“To answer an extremely important question, I’m not just ending my life; I will be ending the lives of others as well,” Stair wrote. Stair left what was called a final “Ember’s Ghost Squad” video, posted just a few hours before the mass murder.

“Be on the lookout … for headlines pertaining to ‘Tunkhannock.’ I’ve been planning to do this for at least three to four months,” he wrote.

One of his videos is called the Westborough High Massacre and labeled “Goodbye.” It starts with an expletive laden introduction that excoriates all of the people who made him feel like he “didn’t matter.” The video shows him with a rope around his neck and then pretending to shoot himself in the head; video of Stair is mixed together with animation.

He also made ominous final statements on Twitter:

His Twitter profile reads, “had to die in order to truly live. Speaking from before and beyond the grave. Just because I think you’re okay today doesn’t mean I won’t hate you tomorrow.”

Randy Stair (Weis Market Shooter) – 02 Andrew Blaze ‘ST’ 04 11 17 My Baby

He wrote, accompanying the release of the Westborough High massacre video, “Ready to die? ‘The Westborough High Massacre’; coming June 7th, 2017. #EGS.” He was also active on Facebook, although his page has been deleted.

Although police labeled the mass shooting a murder-suicide, the shooter was accused of shooting people randomly, according to WKOK-TV.

The names of the victims were listed as Terry Lee Sterling, 63, of Shady Lane Park, South Montrose; Victoria Todd Brong, 26, of Avery Station Road, Factoryville; and Brian Hayes, 47, of Springville, according to Citizens Voice

“Police said Stair was inside the supermarket on 600 Hunter Highway in Eaton Twp., working since 11 p.m. Around 12:50 a.m., Stair grabbed two pistol grip shotguns he had with him in a duffel bag in the store and began shooting, killing three co-workers,” Citizens Voice reported.

2. Stair Was an Active YouTuber Who Had a Following & Left Behind a ‘Suicide Tape’

Stair’s videos include one that “showed him loading shotguns before stuffing them into a duffel bag. In the video, he says, ‘I’ve been stepped on my whole life; not anymore. I’ve had enough of this putrid planet and I’m gonna leave my mark,'” reported PAHomepage.com.

In one post on Twitter, Stair wrote, “When you’re gonna die you gotta die hardcore or not at all!” He also wrote, “The death of a soul isn’t the end of the line; it’s the rebirth of something beautiful.” Stair went by the name “Andrew Blaze” on his prolific social media accounts.

BREAKING: Several members of PSP searching home believed to be of alleged Weis shooter Randy Stair. pic.twitter.com/IHNmf8sSVg — Brian Sheehan (@BSheehanTV) June 8, 2017

A disturbing online diatribe that Stair wrote reads, “I have no regrets for what I may do or what I may have done. I am who I am, and no f***ing human s*** can take that away from me. I’m an ‘EGS’ recruit, you’re worthless f***ing humans. One day you’ll all see things my way; especially when our ghost squad invades your pathetic putrid planet and become our slaves for the rest of your lives. I will not stop, I will not change. I will not cover. I will fight for the squad and do what I’ve set out to do. I’m Andrew F***ing Blaze.”

One friend wrote a lengthy remembrance of Stair on Facebook. He wrote that Stair had become obsessed with ghostly references. He also left behind bizarre videos on YouTube entitled suicide tapes. “It was like I was sent there to do this. I was physically sent here to spread this cause. To start this cult,” he rambled in the video above. “Whatever happens, happens. It’s only the beginning.”

“I just learned several hours ago that an online friend of mine had gone on a shooting rampage at the supermarket where he worked, in Scranton, Pennsylvania, Killing several members of the after hours, overnight shift, before shooting himself dead,” the man wrote. “Randy Stair was a rather attractive young man, who many people loved. Over the past couple years, his behavior had become more and more atypical of his former persona, and he had grown increasingly aloof towards his friends, as well as increasingly grim in his attitude.”

Randy Stair (Weis Market Shooter) – 10 Parents Goodbye 01 June 01, 2017

Stair had a following on YouTube, the online friend wrote, and wrote a lot about the afterlife.

“He was an avid YouTubeer, for most of the past seven years that I had been online acquainted with him. He used to put his videos out under the channel of ‘PioneersProductions,’ and they were mostly humorous, and sometimes a bit mundane and boring. But as his attitude became increasingly serious, somewhat depressed and grim, he started producing an animated channel concerned with things ghostly, otherworldly, and about matters of the afterlife, called ‘EmbersGhostSquad.'”

The friend wasn’t sure before the slayings that anything was that awry, though.

“It’s hard to know, especially with a younger person, how much or how little to intervene in their personal affairs, and counsel them about things that look disturbing to you. Lots of young people go through a sort of grim, or withdrawn, or even a countercultural Goth-Style Period, But it doesn’t necessarily, Or even usually, indicate that they’re on the path towards a psychotic killing spree or suicide. Sometimes when you try to offer advice or counsel to them, during those periods of their lives, it only further serves to alienate them. Randy knew that he had a lot of friends who loved him, and that we were all available to him, and concerned about him. As far as I know, he hadn’t actually left any messages about doing this dreadful act before his last video, last night; the video that I missed,” he wrote.

The man concluded, “There really isn’t too much of a point to this, except that it’s a very sad affair, and we’ve tragically lost Randy, as well as the other people Who were his coworkers, that he took with him. We all love you Randy Robert Stair, and we always will! May your tortured psyche find a process to something better.”

One person made it out of the shooting rampage and was able to call 911 to tell police what was going on, WKOK-TV reported.

The witness was not injured, reported WNEP-TV.

3. Stair Left Behind Disturbing Suicide Notes & Rambling Online Journals That Chronicle a Depressed & Angry State

Through his Twitter page, Stair left behind a troubling written trail of his intentions and warped mind. He even posted links to a massive file containing journals that read like suicide notes.

In the journals, which were posted recently in some cases, he wrote things like, “I’m so ready to die. Two more fun nights and that’s it. I’ve officially accepted that Wednesday night will be the death of me.”

Here’s his final suicide note:

He posted pages and pages online.

He appeared to be conflicted about his gender identity, according to his journals. He wrote in one, “I’m a girl who’s been trapped in a man’s body for two and a half decades, and I need to get the hell out. I don’t belong on this planet, nor have I ever.”

He wrote this on Twitter:

The store was closed when the massacre unfolded, but some overnight workers were inside.

4. Randy Stair Committed Suicide Inside the Store After Spending the First Part of His Shift Blocking Off Exits

What happened inside the Weis grocery store was gruesome and premeditated.

The killer shot the three people and then turned the gun on himself inside the store, according to WGAL-TV.

Three men and one woman were killed in the carnage, reported PAHomepage. According to York Dispatch, Stair, who worked overnight at the store, spent the first part of his shift blocking off exits and entrances without his co-workers having any idea he was planning to slaughter them.

He used pallets and other items to do so, and he fired 59 shots during the shooting rampage, the newspaper reported.

According to PAHomepage, the bomb squad was called to the scene as a precaution.

“Authorities called in a bomb squad to investigate the alleged suspect’s car in the parking lot but ruled the scene all clear,” the news site reported.

5. Weis Market Is a Family Chain With a Series of Stores Throughout the East Coast

BREAKING: @PAStatePolice identify shooter involved in Weis market shooting as Randy Stair, 24, of Dallas, Luzerne County pic.twitter.com/uQ4fsXGY7Q — Eric Deabill (@ericdeabill) June 8, 2017

The Weis Market is located along Hunter Highway near Tunkhannock. It’s located in northern Pennsylvania about 40 minutes from Scranton.

According to its corporate history, Weis Market is a chain of family-owned grocery stores throughout the East Coast that started in 1912.

“Today, Harry’s grandson, Jonathan oversees a company with stores in Pennsylvania, Maryland, New York, New Jersey, Delaware, Virginia and West Virginia. Overall, we employ more than 19,000 associates in our stores, distribution center, corporate office and manufacturing facilities,” the family history on the chain’s website reads.