Man killed, two injured in bear attack near Yellowstone Park

The woman suffered severe bite wounds on her arms, while the injured man was bitten in the leg, local press reported.

Two tents were ripped apart in the unprovoked 4am attack at the Soda Butte campground in the Gallatin National Park, on the northern edge of the famous Montana park.

The area and neighbouring campsites have been evacuated and the injured pair taken to hospital in Cody, Wyoming.

The identities of the three attacked has not been disclosed.

Wildlife officials have boarded airplanes and helicopters to carry out an extensive search for the bear, who is believed to have acted alone.

Montana Fish, Wildlife and Parks Department spokesman Ron Aasheim described the incident as a "random predatory" attack.

Even the copious camping food at the site is not thought to have been motivation, he said, adding that it still not known whether it is a black bear or a grizzly.

The last fatal bear attack in Montana occurred in 2001, when a grizzly mauled and killed a hunter who was butchering an elk, Mr Aasheim said.