Saw flashing lights heading very fast and low over fields and paralell to highway 41 south.On the way home from Evansville my girlfriend was driving, I was in the passenger seat. Her friend was asleep in the back seat. We were just about to get into Vincennes, when we both saw an odd blue light up ahead on the road. We both assumed it was a cop car. I thought it was a light on top of the regal construction building till the light kept moving in flashes toward us till it was eventually over the field, parallel to the right side of the highway. As the light moved past us with each blink it picked up a considerable amount of speed exceeding any aircraft I have seen and I recently saw the blue angels perform in Evansville. The lights appeared to be approxamtely 100 feet from ground level and did not appear to be attached to anything, though it was very dark in the area and again, the light kept blinking and was very hard to focus on as each blink only lasted maybe a tenth of a second. We watched the light pass us and go over the fields heading south toward Princeton/Evansville. We had not been drinking or consuming any drugs. I thought I may be seeing things till my girlfriend confirmed she saw the exact same object.