Object with string of red lights hovers over strip mall then moves over interstate highway before shooting into the sky.

My self and two of my cousins were walking along the street heading west. We were going to have pizza. Ahead of us the houses thin out and there was a section of about two city blocks where there were no houses, just grass lots. Beyond that was a small unused strip mall,some fast food and other types of stores. Beyond that was Interstate 57. As we talked we noticed a string of red lights appear above the dark strip mall. We could make out a form that was darker than the night sky.  To me seemed round with the lights ringing the middle. I would say it was about 30-40 feet across.The object started to move very slowly to the north west. I remember we talked about what it could be, One of my cousins said it must be a helicopter to move so slowly and hover like that. About that time the lights went out. a few moments later a small private airplane crossed the sky to the south east. We could plainly hear its motor. That ruled out a helicopter. The object could still be made out as a dark spot in the sky. It moved west until it reached the interstate highway at which it moved lower and went north along the highway. We could plainly see the traffic moving under it. It went north along roadway until just about the exit/overpass at which time it tilted skyward and in a blur was gone. We were shocked and at this point we knew it was nothing we could point a finger at and say "that was it" We talked excitedly and ran to the pizza place. We had been there maybe three minutes. Standing in line to place our order when a man in his early 20's came running in. He was hysterical. He asked where the phone was, he had just chased a UFO on the interstate. People in line snickered and we stopped talking about it until we were seated. Obviously he had seen the same thing we had.
Witness indicates that the date of the incident is approximate.  PD