Disapeering flying object

My friend and I live in Richmond, Va. and we use to go up to Colonial Beach, which is on the Potomach River and go fishing. The river is a couple of miles wide and on the other side of the river is Maryland. This location is about 10 miles from a militray bas, Fort A.P. Hill. We were fishing behind this seafood restaurant which has a couple of peirs to fish from. On the other peir there was a family of 3. Well, while we were fishing I noticed up in the sky probably 1000 ft. up was a white object flying slowy over the river. It was making no sound. The crazy thing about it was, as it was flying over the river it would just fade out and vanish when it was close to the other side of the river. And amazingly after this would occur, it would re-appear back where it started from. This went on for about 20 minutes. I even ran over to the other pier to show the people there what it was doing. We all saw it in broad daylight on a clear day. The other strange thing was, after it had stopped flying over, a few minutes later a fighter jet flew up through the area that this UFO craft had just been flying in. Has anyone else seen anything like this. Please email me if you have.