Richard Lister says there are eight distinct shots and screams on the video of the shooting
A disgruntled former colleague who allegedly killed a reporter and cameraman during a live broadcast in Virginia is in a critical condition after turning the gun on himself, say authorities.
Alison Parker, 24, and Adam Ward, 27, of CBS affiliate WDBJ, were gunned down during an interview in Smith Mountain Lake, Moneta.
The suspect, Vester Lee Flanagan, was pursued by authorities in a highway car chase before veering off the road and crashing.
The 41-year-old was suffering from a life-threatening gunshot wound, state police said.
Reporter Alison Parker (L) and cameraman Adam Ward died
A recording of the broadcast at Bridgewater Plaza shopping centre showed the camera dropping to the ground as gunfire rang out.
The programme cut back to the studio where Kimberly McBroom, anchorwoman of the Mornin' newscast, was sitting in shock.
The gunman was seen standing over the camera and pointing his weapon down.
Virginia Governor Terry McAuliffe said "disgruntled” Flanagan, of Roanoke, used to work at WDBJ.
Alison Parker with Adam Ward
Flanagan, who used the on-air name Bryce Williams, posted a horrifying video of the shooting to social media.
It showed the gun being aimed at Ms Parker as she conducted her interview, oblivious to what is about to happen.
The footage showed the weapon blasting away at her before she turned and ran screaming.
Alleged shooter Vester Lee Flanagan - also known as Bryce Williams
The Twitter and Facebook accounts of Bryce Williams have been suspended
Flanagan tweeted about filing an Equal Employment Opportunity Commission complaint and accused Ms Parker of having made racist comments.
The news station's general manager, Jeffrey A Marks, said Flanagan was "an unhappy man … who quickly gathered a reputation as someone who was difficult to work with".
He said they fired him two years ago after a series of disputes and had to call police to escort him from the building.
ABC News said on its website it had received a 23-page fax from Bryce Williams sometime overnight.
The broadcaster offered few details about the contents of the document, but said it had turned it over the police.
Governor McAuliffe said earlier the suspect's arrest was "imminent" and police were chasing him on Interstate 64.
Authorities block Booker T. Washington Highway at Bridgewater Plaza, Wednesday, Aug. 26, 2015, in Moneta, Va., after two journalists were fatally shot while broadcasting live from the plaza earlier in the day
"They are right behind him," he said. "They have the licence plate."
Franklin County Sheriff's Office told Sky News the suspect shot three people.
The other victim was the woman being interviewed about local tourism, Vicki Gardner, of the Smith Mountain Lake Chamber of Commerce.
She was shot in the back and is in a stable condition after surgery.
Alison Parker with News Anchor Kimberly McBroom who was visibly shocked as live feed is cut after the shooting
Schools in Franklin County and neighbouring Bedford County, where Moneta is situated, were placed on lockdown after the attack.
Mr Ward was engaged to Melissa Ott, a WDBJ news producer, who was working her last day on Wednesday before going to a new job in Charlotte, North Carolina.
He was planning to move with her.
Ms Parker was dating WDBJ anchor Chris Hurst and the couple had just moved in together.
"We were together almost nine months," he tweeted. "It was the best nine months of our lives."
He added: "She was the most radiant woman I ever met."
WDBJ tweeted: "We love you, Alison and Adam."
White House press secretary Josh Earnest said the shooting was another example of "all too common" gun violence in America and renewed calls for congressional action.