At least 3 crafts circling PA NJ DE area

At 10:10pm I exited my front door after hearing what sounded like hovering helicopters for at least 5-10 minutes.There were 3 elongated crafts circling this area, as well as over in Jersey, further south possibly into Delaware. They didn't hover over 95 at all but were circling the whole area. I couldn't see any light or shadow of the objects themselves and could only see the lights (some flashing and others steady) on the underside.The vehicles were going between significant changes in elevation, made lateral movements, and changes in trajectory. They moved at a steady pace while the radius of their flight broadened and narrowed. The bottoms all had a white, single, centered light towards the front followed by two pairs of lights that changed colors between white, green, and red, and then a tail light. If I had to estimate they were 40 feet long. The planes arriving and leaving nearby Philadelphia International Airport were apparently unaffected and didn't have any engagement or stopping of flights.
Eventually after about an hour, while I could still hear them, they were not visible.