Steve Irwin killed in freak accident at sea

Irwin's wife Terri was in Tasmania at the time of the tragedy and had to be contacted by police with the terrible news.

Dr Ed O'Loughlin was aboard the Emergency Management Queensland Helicopter which was called from Cairns at 11.21am (AEST).

Irwin was being given CPR at Low Isles, off Port Douglas, as the helicopter arrived less than one hour after the incident, but Dr O'Loughlin said nothing could be done to save him.

"It became clear fairly soon that he had non-survivable injuries," Dr O'Loughlin said.

"He had a penetrating injury to the left front of his chest.

"He had lost his pulse and wasn't breathing."

Father-of-two Irwin was swimming at Batt Reef, off the Low Isles, when the tragedy occurred.

Tasmania Police this afternoon confirmed his wife Terri was travelling in the state at the time of the tragedy.

A spokeswoman said police had made contact with Mrs Irwin and "passed on a message relating to the death of her husband".

The Irwins have two children - a daughter, Bindi Sue Irwin, eight, and a three-year-old son, Robert (Bob) Clarence Irwin.

Steve Irwin - known worldwide as the Crocodile Hunter - was famous for his enthusiasm for wildlife and his catchcry "Crikey!".

In an sad twist, it has been reported that his new documentary was aimed at demystifying the stingray.

Irwin's Crocodile Hunter program was first broadcast in 1992 and has been shown around the world on cable network Discovery.

He has also starred in movies and has developed the Australia Zoo wildlife park, north of Brisbane, which was started by his parents Bob and Lyn Irwin. 

Tributes quickly poured in for the larger-than-life character.

"I am quite shocked and distressed at Steve Irwin's sudden, untimely and freakish death," he said.

"It's a huge loss to Australia." 

A Tourism Queensland spokeswoman said the death was shocking and paid tribute to Irwin's "enormous contribution" to his adopted state.

"I don't think we could even estimate how much he brought us through his personality and his profile and his enthusiasm about Queensland," she said.