News anchor thought car backfired when gunman shot colleagues on air

A US news anchor on air when a reporter and her cameraman were murdered on live television said she had no idea her colleagues had just been shot.

Kimberly McBroom was in the studio for WDBJ-TV in Virginia early on Wednesday morning local time when reporter Alison Parker and cameraman Adam Ward were shot dead by former colleague Vester Lee Flanagan during a live interview.

"It sounds so cliché, but it was just a typical day," McBroom told the New York Daily News.

"I thought maybe a car backfired. I thought maybe there were shots in the background. The county is kind of rural.

"(Her being shot) was the very last thing that I thought it was. I heard her screaming. I thought she was scared of the sound. I thought there was some kind of explanation."

Flanagan, 41, was a former reporter for WDBJ7 and used the screen name Bryce Williams before he was fired in 2013.

"Two years. That’s a long time. Nothing could prepare us for this," McBroom said.

Ms Parker, 24,  and Mr Ward, 27, died in the shooting, while it is understood Vicki Gardner, the woman being interviewed by Ms Parker, was shot in the back and has undergone surgery.

Virginia State Police said Flanagan fatally shot himself on Interstate 66 after being ordered to stop during a police pursuit.