The only person to witness the accident that killed Australian wildlife expert Steve Irwin opened up for the first time about the final moments of "The Crocodile Hunter."

"He just sort of calmly looked at me and said, 'I'm dying,'" cameraman Justin Lyons recalled Irwin's last words on the Australian television show "Studio 10."

Lyons said that they were about eight days into a shoot for a documentary called "Ocean's Deadliest" in 2006. The day Irwin died, they had been looking for tiger sharks, when they found a massive stingray, Lyons recalled.

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According to Lyons, just he and Irwin began shooting the stingray in chest-deep water. After a couple minutes of filming, the two stood up and decided to take one last shot of Irwin getting behind the animal, while Lyons would film it swimming away.

"All of a sudden, it propped on its front and started stabbing wildly with its tail, hundreds of strikes within a few seconds," Lyons said. "It probably thought Steve's shadow was a tiger shark, which feeds on them very regularly, so it started attacking."

Lyons said he hadn't been aware the stingray caused any damage until he panned the camera back to Irwin, who was standing in a pool of blood. The stingray's barb had gone through Irwin's chest.

"He thought it had punctured his lung, and he stood up and screamed, 'It's punctured me lung!'"

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The rest of the team threw Irwin back onto their inflatable boat. While Lyons said he performed CPR on Irwin for over an hour, he said medics later pronounced him dead within 10 seconds of looking at him.

According to Lyons, another cameraman on board filmed the entire experience because they had an agreement with Irwin that if he was ever injured, they had to keep filming. Lyons said he doesn't know what happened to the video, but he never wants it to be seen.

"He was so good with animals. Nothing was going to get him," Lyons said. "We thought he was going to live forever."

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