This Asahi Shinbun article has an unmatched right parenthesis in its title:
Surely, Japanese syntactic rules disallow unmatched parenthesis, right?
Asahi Shinbun just made a mistake (in a title no less), correct?
It's not a mistake, it's just a stylistic choice. They do it all the time:
I only spent about 30 seconds looking through headlines to find these examples—I'm not picking out anything rare. You've probably noticed that each one "tags" the article with the name of a prefecture:
Your example "tags" the article as being relevant to 岩手県.