'Crocodile Hunter' Irwin killed
The naturalist worked to protect Australian wildlife
Irwin with tiger cubs
Australian environmentalist and television personality Steve Irwin has died during a diving accident.
Mr Irwin, 44, was killed by a stingray barb to the chest while he was filming an underwater documentary in Queensland's Great Barrier Reef.
Paramedics from the nearby city of Cairns rushed to treat him at the scene but were unable to save him.
Mr Irwin was known for his television show The Crocodile Hunter and his work with native Australian wildlife.
Police in Queensland confirmed the naturalist's death and said his family had been notified. Mr Irwin was married with two young children.
"It is believed that Mr Irwin collapsed after being stung by a stingray at Batt Reef off Port Douglas at about 11:00 am (0100 GMT)," a police statement quoted by AFP news agency said.
"His crew called for medical treatment and the Queensland medical helicopter responded, however Mr Irwin had died."
Mr Irwin had built up what was a small reptile park in Queensland into what is now Australia Zoo, a major centre for Australian wildlife.
Mr Irwin's documentaries were shown around the world
He was famous for handling dangerous creatures such as crocodiles, snakes and spiders, and his documentaries on his work with crocodiles drew a worldwide audience.
But he also courted controversy with a series of stunts.
He sparked outrage across Australia after cradling his one-month-old son a metre away from the reptile during a show at Australia Zoo.
A probe was also launched to investigate whether Mr Irwin and his team interacted too closely with penguins and whales while filming in the Antarctic, but no action was taken.
Foreign Minister Alexander Downer praised Mr Irwin for his work to promote Australia.
"The minister knew him, was fond of him and was very, very appreciative of all the work he'd done to promote Australia overseas," Mr Downer's spokesman said.
Use the form below to send us your tributes to Steve Irwin, some of which may be published.
I was a fan of Steve Irwin's documentaries and the news of his death came as a shock: my brother and I had seen him on TV only a few days ago. I admire what Mr Irwin did for the promotion of Australia abroad, and for the protection of wildlife overall. He surely will be missed, and my condolences and very best wishes go out to his family and to his friends.
Alex Jumpsen, Calgary, Canada
I'm an expat living in Sydney and the whole of our office is in shock. Most of the news sites in Australia have been struggling to cope this afternoon as word of his death has spread. Surely testament to a bloke who was a good old Aussie character. He will be sadly missed.
Anthony, Sydney NSW
This world will miss a brave man like Steve. My sympathy with the family and all the people associated with him.
Ali Hassanali, Sheffield, UK
He typified the Australian spirit, good an ya.
Alan Stewart, Dumfries, Scotland
What kind of man was Steve Irwin? He stopped Australian Government plans to allow rich tourists into the Northern Territory to kill crocodiles for sport. He brought the beauty of nature back to millions through his documentaries. And he showed that if you love doing something, then you should put all your passion into doing it. Nothing less. He was a nice man. A was a kind man. Perhaps, the last real man... gone.
Alan, Brisbane, Australia
Total shock, I will miss his energy on tv, I wish his family all the best.
alec grimshaw, cambridge
Whilst Steve Irwin is probably better known for his antics, the man is fundamentally someone who deeply cared about the environment, and this world. This is a sad loss for the planet, and hopefully people will remember the dedication and love he put in to his work.
Aled Moses, Singapore
It's really tragic to know that Steve Irwin will no longer be there to bring us thrilling documentaries. I'm sure he will be remembered and appreciated worldwide for his work.
We are really really sorry for this tragedy. We could never imagine he could end like this doing what he loved the most and what was best at. All our thoughts are with his family
Adrian, Suceava, Romania
Steve Irwin was an inspiration for many of the younger generation. He will be sadly missed. RIP.
Andrew Fergus, Auckland, New Zealand
He was killed doing what he loved best, yet another informative documentary about some of the worlds most unique wildlife. I always wondered if he'd go too far and a croc would get the better of him, but it's a sad thing to see a great guy go. At least he went out at the top.
Alex, Northampton, UK
Very sad to hear that a good-hearted man has died. He was very well liked by everyone and brought a better understanding of wild animals to the world. For some reason, I feel a strange personal feeling of loss at his death.
Ali Qazi, El Dorado Hills, Calif. USA
It's really shock news to hear. Steve Irwin sudden death is a big loss to the people of the whole World.
Amogh.B, Bangalore, INDIA
As an active member of PETA, I praise Steve Irwin in his efforts to save wildlife. He was an outstanding, intuitive, brave man and will be sadly missed. He has a wonderful wife and two lovely children left behind, but he was living the life he loved and made a difference. he was at times controversial, but changed the way many things are done, so we thank him for that.
amelia bentley, vancouver, Canada
You will be sadly missed. You brought wildlife into our households, not by some stuffy old presenter, but through great humour and fun. My kids will miss you.
Andre van Straaten, East London, South Africa
Nice and lovely guy, I'll miss you.
Andrea Fattinnanzi, Rome Italy
It is really sad to hear about the death of Mr. Irwin. He proved his mettle while filming the famous show "The Crocodile Hunter". With his peculiar charm and sense of duty to wild life, he attracted many a crowds. Wildlife would not be the same without him.
Ahmad R. Shahid, Islamabad / Pakistan
This is a great loss to all, my deepest heartfelt wishes go out to Steve's family.
Andrew A'Barrow, Poole Dorset
An amazing man, special. my condolences to his family
Angus Macdonald, Cardiff UK
My condolences to Steve's family over such a huge loss. Steve's videos were extremely beneficial for use in teaching students about different animals and places around the world. He made learning fun for my students and many others. He will be sorely missed. He was a trailblazer and opened the world to many people. Thanks Steve !!!
Austin Sloan, Spokane, Washington
It is sad to read about the untimely demise of Steve Irwin. He was a person who brought awareness from a true conservationist's point about the diversity and importance of the various creatures this planet supports to a whole generation. Deep felt condolences to his family and the people dear to him.
arun, memphis, Tn
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