A large lightning bolt appeared to come out of a white truck horizontally and strike a power pole.

I was returning home from work on a summer day, as it was only just beginning to get dark.  I was just outside the city limits of Pittsburg, KS, on extended 4th street.  My car was following another car and an unmarked white delivery-style truck was approaching us from the west.  
We were a few blocks from the trailer park that I lived in, when a large lightening bolt appeared to come horizontally out of the back-side of the white truck and struck a power pole.  The car in front of me kept going and I could not tell if they noticed this extremely unusual event.  The white truck continued on, giving no indication of anything else unusual.  I was scared to meet the truck on the highway, but did not have any other choice and passed the truck without further incident.  I drove into the trailer park as the neighbors were coming out of their homes, wondering why their electricity had just shut off.  I remember someone asking me what I had done, as it seemed that the power went off just as I drove in the neighborhood.
I would sincerely like to know what this could have been, as I have puzzled over this for over 20 years.  The date is approximate.  I remember the approximate time of day and that it must have been the middle of summer as the sun had not set.  There were no clouds that I remember- and definately no thunderstorms!  It was a clear, calm evening.
I'm not sure that this qualifies as a UFO sighting, but I remember at the time that people were saying that the government was moving secret objects in unmarked trucks.  This is the only place that I have ever thought might be able to provide me with an answer.
Witness states that the date of the incident is approximate.  PD