Rotating circular objects seen in Portland, Oregon

There were rotating circles in the sky. They looked like spotlights but there were no visible sources of flashlights or any other lights nearby. They rotated and spun, went together, spun together, and then split apart to repeat the sequence. At the beginning, there were only three lights, but a fourth came around 8:45. It was completely dark outside. They continued spinning, rotating, and generally being odd until about 9:00, at which point we were too far away to see them.