Pulled over by a ufo using police lights

I was enroute to my father's house one Sun. night on a rural road when I noticed blue, revolving police lights in my rear view mirrow. Thinking I had perhaps instigated a traffic violation, I pulled over. I looked rearward and saw nothing, no police car, nothing. I then looked to my immediate right and saw an immense ufo hovering over the tree tops. It appeared to be about 50 yds. or more in diameter and was oval in shape. It seemed to be made of a shiny metal similiar to aluminum. The craft was very luminous. The object just sat there,no noise or any sounds. I looked for approximately five minutes and left. I looked backward to see if it was still there but it had vanished. My feelings were that they wanted me to see the craft. It was so close that I could have hit it with a rock. I've never had any sightings since then.
Date is approximate.  PD