ROANOKE, Va. (CBS/AP) — The gunman who killed a Virginia TV news reporter and cameraman during a live report said in a 23-page manifesto that he committed the act in reaction to the shooting at Emanuel AME Church in Charleston, South Carolina that killed nine black parishioners as well as years of racial and sexual discrimination.

Vester Lee Flanagan II – who went by the name Bryce Williams – was a former co-worker of reporter Alison Parker and cameraman Adam Ward at WDBJ-TV in Roanoke. Virginia authorities say he was the gunman who fatally shot Parker and Ward during a live news report around 6:45 a.m.

Flanagan died of a self-inflicted gun-shot wound.

Flanagan titled the document “Suicide Note for Friends and Family.”

“Why did I do it? I put down a deposit for a gun on 6/19/15. The Church shooting in Charleston happened on 6/17/15,” he wrote in the manifesto, according to ABC News. “What sent me over the top was the church shooting. And my hollow point bullets have the victims’ initials on them.”

Flanagan did not say which victims he was referring to.

In the manifesto, Flanagan claims he was attacked for being a gay, black man, and that he suffered racial and sexual discrimination at work.

“Yes, it will sound like I am angry…I am. And I have every right to be. But when I leave this Earth, the only emotion I want to feel is peace,” he wrote.

The manifesto continued, “The church shooting was the tipping point…but my anger has been building steadily…I’ve been a human powder keg for a while…just waiting to go BOOM!!!!”

Flanagan also said in the note that Virginia Tech shooter, Seung Hui Cho, was “his boy” and mentioned the Columbine High School shooting.

“Also, I was influenced by Seung-Hui Cho. That’s my boy right there. He got NEARLY double the amount that Eric Harris and Dylann Klebold got….just sayin,” he wrote.

Flanagan added that Jehovah told him to act.

Jeffrey Marks, WDBJ’s president and general manager, said Flanagan had to be escorted by police out of the station when he was fired. Marks described him as “an unhappy man” and “difficult to work with,” always “looking out for people to say things he could take offense to.”

“Eventually after many incidents of his anger coming to the fore, we dismissed him. He did not take that well,” Marks explained.

Video posted hours after the shooting on Bryce Williams’ Twitter account and Facebook page showed an outstretched arm holding the handgun and firing repeatedly at Parker as she tried to run away.

The shooter appeared to walk up to the victims and stand a few feet away from them while holding the weapon. The three, in the midst of a live TV interview, do not seem to notice the gunman, who doesn’t start shooting until Ward points the camera at Parker.

Ward was engaged to a producer at the station, Melissa Ott, who was celebrating her last day on the job and was in the control room, watching it live, as the shooting unfolded, Marks said.

Tweets posted on Williams’ Twitter account Wednesday described workplace conflicts with both victims. They say Williams filed a complaint with the Equal Employment Opportunity Commission against Parker, and that Ward had reported Williams to human resources.

Marks said Williams alleged that other employees made racially tinged comments to him, but said his EEOC claim was dismissed and none of his allegations could be corroborated.

“We think they were fabricated,” Marks said.

“This gentleman was disturbed at way things had turned out at some point in his life. Things were spiraling out of control,” Franklin County Sheriff W.Q. “Bill” Overton Jr. said at a news conference.

Both the victims were romantically involved with other employees at the station, according to Parker’s boyfriend, WDBJ anchor Chris Hurst. He wrote online that they hadn’t shared their relationship publicly but “were very much in love.” He said they had just moved in together and wanted to get married. “I am numb,” he said.

The shooting happened around 6:45 a.m. at Bridgewater Plaza in Franklin County, as Parker interviewed Gardner about the upcoming 50th anniversary festivities for Smith Mountain Lake, a local tourism destination.

Ward, 27, graduated from Virginia Tech and was engaged to a producer at the station, Melissa Ott, said WDBJ spokesman Mike Morgan.

“Adam was our go-to guy. He pretty much was available to do anything that we asked,” Morgan said. “He did live shots during our morning show for several years.”

Parker had just turned 24 and had joined the station as an intern after attending James Madison University, where she was the editor of the school’s newspaper, The Breeze. According to her Facebook page, Parker spent most of her life outside Martinsville, Virginia. She was an avid kayaker and attended community theater events in her spare time.

The station is based in Roanoke, Virginia, and serves the southwest and central part of the state. The shootings happened at a mall just off Smith Mountain Lake in Moneta, about 25 miles southeast of Roanoke.

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