A row of lights in the night sky vanished after they split formation.

I reside in Los Angeles, California. What I saw was not recent, but about ten or eleven years ago. 
I was at a party at an apartment complex in Burbank, California. It was anywhere between 8 and 9pm at night. 
I remember standing outside in the courtyard of the complex and looking up to the eastern sky. I noticed what I thought to be a row of stars lined up vertically, straight up and down. 
At first I thought to myself it was the belt of Orion, but for some reason it didn’t look right to me. Within a matter of seconds, the bottom two stars (lights) began to move. The middle one going left and the bottom moving to the right. 
At first they started to move apart slowly, but then they began to increase in speed. They both started to move really quickly in circles weaving across eachother, all the while staying in the same general location they started in. They never moved very far from their original location. 
Eventually they disappeared into the sky. When that happened, the remaining star began to move in the same rapid way and making circular movements, also eventually disappearing into the sky. 
The whole thing could not have lasted for more than one minute and thirty seconds, since I first noticed them. It was one of the most mysterious and fascinating things I’d ever seen.
At first I thought I had truly seen a UFO. To this day I really don’t know what it was, but what I saw was way to remarkable to be anything different.