From a patio in a suburban neighborhood, the primary witness observed a small, bright red light rising from the horizon in the WSW direction. The direction corresponded approximately with that regularly observed for commercial airlines/cargo aircraft on approach to MDW or ORD. The light approached from WSW, heading NE at an apparent velocity at least 4-5 times the apparent velocity of a typical commercial aircraft seen on approach from that direction. At first, the primary witness considered that the light was a low aircraft without standard landing or navigational illumination. There seemed to be a faint hiss from the light as it approached. As it reached between 30 and 45 degrees in elevation above the horizon, the light instantly decreased in apparent velocity and changed heading N. The light then continued on at the reduced velocity until it reached a position to the NW of the observation position (still at similar angle of elevation) and appeared to hover.As the light began to hover, the witness observed two more identical lights in close formation with each other follow the same approach and pattern at similar velocity. The faint hissing sound also seemed to emanate from these. As the pair of lights approached the apparent waypoint for change to a N heading, the witness observed a commercial aircraft at typical approach altitude from the SSE, flying directly overhead, presumably on approach to MDW, and with standard landing and navigation lights. This commercial aircraft should have had clear observation of the pair of lights, and likely the fourth light. The dull roar of the commercial aircraft was clearly audible and was vastly different than the faint sound heard from the lights by the primary witness. The witness also noticed that the first light had apparently disappeared as the pair of lights progressed along the same N heading. As the pair of lights began to hover in the same NW location as the first light had, a fourth light appeared from the same location along the horizon, proceeded along the same route, and at similar velocity to the first three.At this point, the primary witness called a second witness from the residence to confirm what was being observed. The second witness observed the two lights in formation appear to hover in the same location that the primary witness had observed the first light hover. The secondary witness did not observe the entire approach of the fourth light from the horizon, but did observe its change in heading to follow the pair of lights N. Both observers witnessed the pair of lights either reduce in illumination, or proceed at increased velocity N, until they disappeared. The secondary witness returned to the inside of the residence as the fourth light progressed along the path N. The primary witness then observed the fourth light appear to hover in the same location as the first light and the pair of lights had hovered. For 1-2 minutes, the light seemingly hovered in place, with slight random movement. After hovering, the light began to diminish as the pair had, again either extinguishing or moving off at rapid velocity directly away from the observer, to the N.The witness also observed another, presumably commercial (based on apparent landing and navigation lights), aircraft in the distance. This second commercial aircraft appeared in the NNW and appeared to be following an E heading, possibly on approach to ORD. From the point of observation, this aircraft and the fourth light appeared to have intersecting paths. As the fourth light faded from view completely, there was approximately 3-5 degrees of angle between it and the commercial aircraft, with the commercial aircraft still to the W of the fourth light. For approximately 5 minutes following the event, the primary witness continued to scan for additional lights, but none appeared. As the fourth light was moving off to the N, a third commercial aircraft appeared on the horizon from the same location as the four lights, to the WSW of the observation position.At the closest approach (as each light changed heading N), the red lights appeared in size equal to landing lights on a commercial aircraft at standard to low approach. The red lights did not blink and no strobe or steady lights of any color appeared to accompany the lights. The intensities (though not the color) of the lights were similar to a commercial aircraft landing light on low approach and did not appreciably vary, except with distance as they approached from the WSW and appeared to depart to the N.The primary witness wears prescription eyeglasses for distance correction and had them on for the entire event. The secondary witness wears contact lenses for distance correction and had them in for the entire event. The secondary witness did not indicate noticing the faint hissing sound with any of the lights that the primary witness heard. Neither witness was under the influence of an intoxicant during the event. Over the course of the event, the primary witness observed cloud-to-cloud lightning strokes at altitude far to the SSW. The distance was great enough that thunder did not perceptibly report at the observation location from the strokes. Fireworks had been launched in the vicinity of the observation location during the course of the evening, though the primary witness does not recall hearing the report of mortars at any time during the event and each of the lights lasted far longer than any pyrotechnic device the primary and secondary witnesses have previously observed and did not wax or wane appreciably in intensity. There is no doubt by the primary and secondary witnesses that the lights were some type of aircraft, and not a pyrotechnic effect.In contrast to standard aircraft, the lights displayed the ability to move at high velocity and make rapid changes in velocity. The ability to, apparently, hover is not common among fixed-wing aircraft, yet the apparent velocity seemed to the primary witness to be too great for a rotor aircraft. If the lights were at low altitude (to explain the high velocity from the horizon), they did not emit a loud noise as would be expected from a rotor or fixed-wing aircraft. The primary and secondary witnesses are familiar with military helicopters that operate periodically in the local airspace. These aircraft (Sikorsky UH-60 Black Hawks) have always been readily audible both during the day and at night. If the lights were aircraft with STOL/VTOL capabilities, they did not emit the expected sound of a jet turbine engine.