Northbound saucer-shaped objects zigzag across Southern California

As I sat on the front porch at my parent’s house, which faces north, I happened to look east toward the LA Coliseum, and something high up in the sky caught my attention. I saw a shiny, saucer-shaped object sitting in the sky. Then, a few seconds later, two more of these objects came cruising slowly to where the first one was apparently waiting because a few seconds later, the first one suddenly shot away northward in a zigzagging motion that took two or three really quick direction changes. Then it would come to a dead, sudden stop, and just sit there while the two following came slowly over to where it was, but in a straight line.
I watched them do this about 4 times, moving north across Southern California, toward and past Pasadena. I watched approximately 2 minutes.