(GlobalSecurity.org link)
I believe the key words here are: "...what appears to be flames shooting out the back." I imagine the people who live in the area are quite familiar with what a missile launch looks like.
(YouTube link)
Flying above Los Angeles, the crew aboard a helicopter estimated the missile was fired approximately 35 west out to sea, north of Catalina Island. Vandenburg AFB, which is in Santa Barbara county and north of LA, holds a ballistic missile defense program, a system to defend the United States against missile attacks. The system is capable of defeating ballistic missiles of all ranges in all phases of flight. If it was not a show of strength at some target in the Pacific, perhaps it's because we were intercepting a missile launched at us. I'm just speculating, but you gotta wonder!
