Rural Japan is seeing a spike in bear attacks triggered by what officials believe is a shortage of food in the animals' mountain habitats.

The Environment Ministry says bears have attacked 84 people — killing four — from April to September this year, surpassing last year's total of 64 attacks.

Ministry official Shinichi Oyama said Thursday that the increase is alarming.

The attacks have drawn national attention and TV news broadcasts have shown bears walking down residential streets or climbing trees near houses.

The attacks have been limited so far to the less-populated northern and central parts of Japan. In the north, police said a bear broke into a nursing home last week and seriously injured a woman.