Green light moving at really high speeds crosses night sky and disapears

I was down at our citys park which is right off of Lake St.Clair. Me and my friend were sitting smoking in the parking lot when the whole place lit up.  It scared the crap out of me because I thought it was a cop pulling in. We where not old enough to be smoking, and the park was closed.  There was nobody pulling in.  I looked up to see what appeared in my line of vision about half of an inch wide burst of green light traveling at increadible speed cross about 40 degrees of the night sky about 45 degrees off of the horizon in about 3 to 5 seconds just off the shore of the lake. The briliant flash of light lit up the whole parking lot. As it crossed the sky it went from lager to smaller and then disapeared but had almost an after image behind it for about half a second. That is when it occured to me that it was much to large and traveling way to fast to be a meteorite.
The description is not inconsistent with a meteoritic event.  Meteors traditionally are traveling at many tens of miles per second when they strike the Earth's atmosphere.  Date may be approximate, although the witness does not indicate that fact.  PD