This story is peculiarly similar to the recent one about a brown bear attack in Alaska. In both cases, teens were on a wilderness expedition. But whereas the Alaska case involved a sow defending her cubs against a perceived human threat, this one looks like a bear in predatory mode.
Attacks by polar bears are rare because their range is largely outside ours. A high percentage of their attacks are predatory.
'Hungry' polar bear mauls British tourist to death in horrific attack | News:
"A British boy aged 17 was mauled to death today when a polar bear attacked a group of students on a remote Norwegian island.
Four others, including two teenage boys, were injured by the starving animal at 7.36am on Spitzbergen."
UPDATE: More information and a video interview with a survivor's father.
Thanks to Steve V. for the news tip.