I was driving down a stretch of highway, just outside of regina. I was about an hour or so from reaching moosejaw. With me was my mother, and two sisters. In the distance ahead, I could see what looked to be a fog or smoke. I asked my mother if she could see it as well, and she to saw it. I thought that It may be smoke from a brush fire. As the car entered the smoke, or fog, I noticed that there was no smell to it at all. I found that to be very strange. If It was smoke, you would have smelled it. All of sudden on the the left hand side of the road, in the ditch area, appeared what looked to a spinning fireball. The center of the ball was a darkish orange, the outer part of it was like a lighter orange, almost yellow. All of us seen it, and were very shocked by it's quick appearance. I was not to sure what to think about it. But my thoughts of wonder, soon turned to fear, when I noticed the ball was about two feet above the brush in the ditch. So including the depth of the ditch, this ball was hovering about six feet off the ground. There was no fire, just a hovering bright ball, letting off a myst of some sort. It wasn't a hard decision, to step on the gas, and get away from that area as quickly as possible. If that wasn't strange enough, what happened afterwards was beyond crazy. We had cleared the haze, or myst, what ever it was. In the distance behind me, I could see in my rear view mirror, two head lights. I remember thinking to myself, did they see what we just saw? The next thing I knew, the headlights were right at the back of the car. I thought again to myself, this guy is movin. So i moved as far to the right as I possibly could, to let him pass. Along side of my car, came a black semi trailer. No markings, with blacked out windows. This truck pulled in front of the car, and reduced it's speed so quickly, I had to slam on my breaks. I though maybe he had experianced some problems or something. So I went to pass him. he swerved right into the lane I was going to make the pass in, almost hitting the front of my car. When I reduced my speed and went back into the right hand lane, the truck did the exact same thing. Out of no where, from the top of the trailer, two lights appeared, they looked like what may be dock lights, that a semi driver may use to back into a bay. They were bright, and hurt the eyes. Then from the top and sides of the trailer, a unknown substance was being released towards the car. I remember not being able to see, and almost bringing the car to a complete stop. The substance cleared, and to my surprise, the trailer was right in front of me, with no more bright lights. I remember switching lanes, and speeding as fast as I could past the truck. I looked in the mirror, and saw the headlights behind me. When I took a second glance back. They were gone. We soon after pulled into the truck stop in Moosejaw. I remember getting out of the car, and waiting for the semi to come up the highway, it never did show. As I said at the start, we were an hour or so out of Moosejaw when this happened. When I looked at my watch in the truck stop, nearly four hours had passed.((NUFORC Note: Date is approximate. PD))