ANCHORAGE — A hiker in Alaska's Denali National Park photographed a grizzly bear for at least eight minutes before the bear mauled and killed him in the first fatal attack in the park's history, officials said Saturday.

Investigators have recovered the camera and looked at the photographs, which show the bear grazing and not acting aggressively before the attack, Denali Park Superintendent Paul Anderson said.

The hiker was backpacking alone along the Toklat River on Friday afternoon when he came within 50 yards of the bear, far closer than the quarter-mile of separation required by park rules, officials said.

Investigators have identified the man but won't release his name until they've notified his family. They said he's a U.S. citizen but declined to release any information about him.

Rangers were hoping to recover his remains later Saturday after ensuring the scene was safe. Several other bears have been seen in the area.

Officials learned of the attack after hikers stumbled upon an abandoned backpack along the river about three miles from a rest area on Friday afternoon. The hikers also saw torn clothing and blood. They immediately hiked back and alerted park staff.

Rangers in a helicopter saw a large male grizzly bear sitting on the hiker's remains, which they called a "food cache" in the underbrush about 100 to 150 yards from the site of the attack on Friday.

A state trooper shot and killed the bear on Saturday, and investigators will examine its stomach contents and use other tests to confirm it's the animal that killed the hiker.