Bryce Williams, whose legal name was Vester Lee Flanagan, shot dead Alison Parker and Adam Ward as they carried out an interview for WDBJ on Wednesday.
Two hours later, he reportedly faced the manifesto to the network. In it, he referred to Dylann Roof, who opened fire at an African-American in Charleston earlier this summer, killing nine people.
"Why did I do it? I put down a deposit for a gun on 6/19/15," he wrote, ABC reported. "The Church shooting in Charleston happened on 6/17/15…
"What sent me over the top was the church shooting. And my hollow point bullets have the victims’ initials on them."
In the letter, he said he had suffered racial discrimination, sexual harrassment and bullying at work, ABC reported.
He wrote: "I’ve been a human powder keg for a while…just waiting to go BOOM!!!!”
After he murdered the news team on Wednesday, he fatally shot himself and later died in hospital.
It has emerged that he was raised a Jehovah’s Witness in Northern California and was crowned homecoming prince at his Oakland high school.
He started out as a model before securing on-air reporting jobs in several cities in the South. He eventually moved to Virginia to work for WDBJ.
After working for WTWC in Tallahassee, Florida, he filed a lawsuit alleging he was fired after filing a “race discrimination and retaliation” complaint.
In his lawsuit, he said he was fired after complaining he had been targeted because of his race. He claimed that one producer called him a “monkey.”
But the station denied he was fired because of his complaint and instead insisted it was the result of the decision for corporate belt-tightening.
After joining WDBJ in Roanoke, he was also fired.
Jeffrey Marks, the network's president and general manager, called Williams "an unhappy man" who had to be escorted by police out of the station. He said Williams was always looking for things he could be offended by.
"Eventually after many incidents of his anger ... we dismissed him. He did not take that well," Marks said.
This is the suspected shooter, Vester Flanigan, who is also known as Bryce Williams. He is a former WDBJ7 employee. pic.twitter.com/ngXrqHVLmw— WDBJ7 (@WDBJ7) August 26, 2015
Williams also apparently tweeted about the shooting, accusing Parker of making racist comments.
“They hired her after that???” he wrote.
He also posted two videos showing him approaching the crew and pulling the trigger.
The Twitter account has since been suspended.
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