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• Reporter, cameraman killed on air; gunman dies
• US on-air shooting: A timeline of events
Just two days after the tragedy in Charleston, Flanagan bought a gun, he said.
"What sent me over the top was the church shooting. And my hollow point bullets have the victims' initials on them."
A little over three months later, Alison Parker and Adam Ward would be killed - slaughtered on live TV outside Roanoke.
Flanagan also mentions the Virginia Tech mass shooter Seung Hui Cho.
He calls the madman "his boy" while also applauding the Columbine High School killers.
"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."
Also in the letter, which he at one point refers to as his 'Suicide Note for Friends and Family', Flanagan lists grievances including racial discrimination at work as well as sexual harassment and bullying.
He writes that he's been attacked by black men and white women as he discusses the difficulties of going through life as a gay man of colour.
While Flanagan says the Charleston shootings were the tipping point for him, it's clear he's been unwell for some time - and he admits as much.
"My anger has been building steadily...I've been a human powder keg for a while...just waiting to go BOOM!!!!'
Hours after he sent ABC News the fax, Flanagan reached out again, this time by phone.
He told them he'd killed two people that morning and that the cops were after him and "all over the place".
"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. Overton Jr. later said at a news conference.
Flanagan, who went by Bryce Williams on the air, sued a North Florida station in 2000 claiming one of his bosses called him a "monkey" among other offences.
Before he killed Parker and Ward, Flanagan accused Parker of being racist as the horrific crime played out in real time.
"Alison made racist comments," he insisted on Twitter, as police pursued him down a Virginia highway. "They hired her after that???"
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 offence to".
"Eventually after many incidents of his anger...we dismissed him. He did not take that well," Marks explained.
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.
ABC News reported on its website that the network received a 23-page fax from someone claiming to be Williams. The network said the fax was turned over to authorities, and did not elaborate on its contents.
One of the tweets he sent after allegedly shooting Parker and Ward appeared to suggest the cameraman was among the people who disliked working alongside Flanagan.
"Adam went to HR on me after working with me one time!" wrote Flanagan.
Flanagan, who was a multimedia reporter for the station, left WDBJ at their behest. Prior to his two years reporting at WDBJ, he had worked at several news stations across the country.
According to his LinkedIn page, Flanagan had stints at WTWC in Florida; WTOC in Savannah, Georgia; WNCT in Greenville, North Carolina; KMID in Midland-Odessa, Texas; and KPIX in San Francisco.
Newsweek reported that Flanagan filed a discrimination lawsuit against WTWC-TV in 2000, which alleged that a producer at the station called him a "monkey".
Flanagan also alleged in the suit that an "official" at the station joked that a black murder suspect with gold and green grills had 'collared greens' stuck in his teeth, reports TMZ.
He also claims in the suit that he heard a manager tell another black employee to 'stop talking ebonics.'
Flanagan also claimed that an unnamed white supervisor at the station said black people were lazy because they did not take advantage of scholarships to attend college.
The station generally denied the allegations of discrimination and said it had legitimate reasons for ending Flanagan's employment, including poor performance, misbehavior with regard to co-workers, refusal to follow directions, use of profanity and budgetary reasons.
- Daily Mail