I will add a note about this case file. I see a photo (not related to the case at hand) is referenced, taken June 22, 2011, in Russia.
Growing up within view of Vandenberg launches, this definitely appears to be the remnants left in the sky after a missile launch. I researched, and it appears that on that same day, June 22, 2011, a missile was launched from Minot AFB -- a intercontental ballistic missile. One in the same?
Worth noting: http://www.minot.af.mil/news/story.asp?id=123261062