Enormous strobing rectangle lights moving across the sky at extremely high speed

Huge.  I mean absolutely enormous.  The light flashing appeared to be as large as 15-20 Tower beacons.  White not red.  It flew in from the direction of S. Louisiana St. towards S. Compton.  Was extremely loud, and sounded like a missle.  Was flashing like a strobe light and moved faster than any jet or airplane I've ever seen.  It took literally seconds to move from out of sight in one direction to out of sight in the other direction.  It is cloudy outside.  No stars to be mistaken, and the light was still so bright it was blinding, making it hard to even see the shape.  Immediately afterwards, you could hear aircraft in the sky, as if trailing it.
Witness elects to remain totally anonymous; provides no contact information.  PD