The founder of an animal welfare group which campaigns for the protection of grizzly bears, has been killed by a bear during a camping trip in Alaska.
The Katmai National Park is a prime viewing spot for brown bears
The bodies of Timothy Treadwell, 46, and his camping companion Amie Huguenard, 37, were found in the Katmai National Park.
Mr Treadwell's website said he had lived peacefully with Alaskan grizzlies since the late 1980s "without weapons".
Park rangers later killed two aggressive bears they discovered at the campsite and closed the park.
Mr Treadwell founded the Grizzly People group to help preserve bears and their wilderness habitat.
"Our goal is to elevate the grizzly to the kindred state of the whale and dolphin through supportive education in the hopes that humans will learn to live in peace with the bear, wilderness and fellow humans," according to the Grizzly People website.
It says Mr Treadwell "immerses himself among these fascinating animals".
"Living without weapons or fire, Treadwell studies the animals, all the while protecting them from humans who would kill them for trophies and their valuable body parts," it says.
In an interview with actor and environmentalist Leonardo DiCaprio's website, Mr Treadwell said he was a former juvenile delinquent but working with and studying bears had changed him.
During his time in the wild he videoed and photographed the creatures and was the co-author of a book entitled Among Grizzlies: Living with Wild Bears in Alaska.
King of beasts
Introducing his book Mr Treadwell says: "The grizzly bear is one of a very few remaining on earth that can kill a human in physical combat. It can decapitate with a single swipe, or grotesquely disfigure a person in rapid order.
"Within the last wilderness areas where they dwell, they are the undisputed king of all beasts, I know this all very well. My name is Timothy Treadwell, and I live with the wild grizzly."
Mr Treadwell's death was the first fatal bear attack in Katmai for at least
15 years, according to the Park Service.
The park is a key site for viewing huge brown bears, the coastal cousins of grizzlies, as they feast on salmon.
In the past, Mr Treadwell's behaviour was criticised by Park Service officials and biologists, who expressed concern for his safety and the message he was sending out to others.