Lyons was the only person with "Crocodile Hunter" Steve Irwin, Australia's famed wildlife expert and television personality, when he was stabbed in the chest by a stingray barb in September 2006.
Described as Irwin's best friend, Lyons said he and the Croc Hunter were filming for a documentary, Ocean's Deadliest, when they saw a "massive" stingray floating away.
"I had the camera on, I thought this is going to be a great shot, and all of sudden it propped on its front and started stabbing wildly, hundreds of strikes in a few seconds," Lyons said.
"I panned with the camera as the stingray swam away and I didn't know it had caused any damage. It was only when I panned the camera back that I saw Steve standing in a huge pool of blood," he added.
"I was saying to him things like 'think of your kids Steve, hang on, hang on, hang on,' and he calmly looked up at me and said 'I'm dying' and that was the last thing he said."
Lyons said that he doesn't know what happened to his footage of the incident, but said he didn't want anyone to see it "out of respect for his family."
[News.com.au, Sydney Morning Herald]