Back in 1966 in New Jersey, the ice on the Wanaque Reservoir was 37" thick. A Monastery on Skyline Drive saw 7 saucer type craft fly over the mountains; every small country town up the seven mile long reservoir spotted the exact same thing.
The next morning there were seven 50' diameter cirlcles, which were actually holes in the ice, running up the middle of the reservoir. The one mile stretch of straight roadway by the reservoir was lined wih news crews and hundreds of onlookers for over a week.
Nothing ever came out of the water, yet no one ever sent divers in to investigate.
Being much younger at that time we tried setting roman candles up near the ice ring edge to try to make them come back up, but to no avail.
Prior to this something also cut a 50 mile stretch of tall pine trees in the same area, West Milford, New Jersey. You could see up and down over two ridges of solid pine trees, cut clean to the ground as if by a roller cutter or something. This was around the same time 1965 or 1966