Payton Gendron recorded his plans to carry out the racial massacre in East Buffalo for months in a chat on the Discord social media platform, reports show. Just 30 minutes before the white supremacist fired his first set of rounds in the Tops Friendly Markets in the Black neighborhood Saturday, he invited a small group of people to the private chat room to see his plans.

Gendron’s goal was to kill three dozen Black people, he said in the messages. No one in the chatroom alerted authorities, according to reports. He killed 10 Black people on Saturday. 

“What we know at this time is that a private, invite-only server was created by the suspect to serve as a personal diary chat log,” Discord officials said in a statement.

“Approximately 30 minutes prior to the attack, however, a small group of people were invited to and joined the server. Before that, our records indicate no other people saw the diary chat log in this private server.”

Gendron also live streamed the shooting rampage and posted a 180-page manifesto online.

The Washington Post reviewed 672 pages of Discord messages posted by someone with the same handle used by Gendron on other social media platforms. The messages included selfies of the suspect.

The paper also verified a speeding ticket that Gendron mentioned he received. The user referenced Gendron’s mental health evaluation last June, which was recorded by New York State Police, according to reports.

The 18-year-old said in the messages he lied when he told medical evaluators his threat to commit a murder-suicide when he graduated high school was a joke. He believed the decision allowed him to stay off the FBI’s radar.

“It was not a joke,” he said in the Discord messages. “I wrote that down because that’s what I was planning to do.”

On April 29, a copy of the first installment of the Gendron’s message was uploaded on the file-hosting platform MediaFire. The Washington Post reported that it was not available to download until Monday.

The second batch of messages was posted on Thursday. MediaFire has removed the document and disabled the account. The platform’s chief executive said the records would be kept for law enforcement.

“This is where I’m gonna end it, thanks for the fun,” the last message says.

The records on Discord go back as far as November, according to reports. They show that Gendron vowed in December to kill “replacers.”

He selected the Tops store in Buffalo by February after considering attacking sites in Rochester. He also planned on targeting two other spots in Buffalo.

According to reports, the assailant estimated how many Black people he could kill between each location and worked out the distance and how much time he would need for each shooting.

The messages also revealed that the assailant considered carrying on the rampage at a Black school or church but changed his mind.

“I would consider breaking into a Buffalo elementary school, but those places are locked up tight, plus I get a strange feeling when thinking avout massacreing children,” he wrote.

In addition to those killed, three people were injured in the attack on Saturday before police officers arrested Gendron. Witnesses said he had taken off his tactical gear and turned the gun to his neck before police took him down.

A portion of a live stream of the attack showed Gendron paused after pointing his assault rifle at a white man in the store to apologize, and walked away. A longer version of the video showed Gendron had already shot about four or five people, shooting one woman on the floor twice.

The white supremacist journaled three visits to the Tops store on March 8 where a security guard confronted him. He told the guard he was “collecting consensus data,” according to reports. In addition to two security guards, he counted 53 Black people in the supermarket that day and six white people.

Gendron also feared that his parents would uncover his plan. He wrote about hiding his guns in his bedroom and clothes in his car. The suspect said he bought and sold silver coins to acquire the ammunition for the massacre. 

When Gendron’s parents saw a speeding ticket from his reconnaissance visit to the store 200 miles away from his home, he told his father on March 26 that he skipped school to go on a hike at a state park, according to reports.

Gendron had secretly dropped out of community college, however. Fearing that his parents could have caught on to his plan, Gendron wrote that he wished he had launched the attack right away

“My parents know little about me,” he wrote on Feb. 22. “They don’t know about the hundreds of silver ounces I’ve had, or the hundreds of dollars I’ve spent on ammo. They don’t know that I spent close to $1000 on random military s—. They don’t even know I own a shotgun or an AR-15, or illegal magazines.”