Kumamoto Prefecture
proper noun
Bear origin prefecture is Kumamoto Prefecture. Probably best to learn this meaning via the reading. Also, you should look up Kumamon of Kumamoto-ken.
The reading is 熊's reading, the alternate "origin" 本 reading, and the reading for 県.
夜行バスは、熊本県で発生した事故のため一時不通になった。
The night bus service was temporarily suspended because of an accident in Kumamoto prefecture.