UFO Sighting in Wisconsin on May 31st 1968 – mass sighting (>150 people reported) over lake; same night entity in back yard

Friends and I were having a sleepover. Big brother babysitting inside. Parents on vacation. Sighting of strange erratic, controlled movements of a bright "star" looking out 17 miles away over the Lake toward the east....just star-gazing. Over 150 people reported this sighting and phoned that night and next morning to the local radio station. All KINDS of erratic flight under direct control of SOMEONE.....very weird! Also saw small whitish figure in parents' bushes - which we interpreted as a ghost...7th or 8th graders we were. We went inside. Not long after the sightings of both things, we had two "FBI Agents" at our parents' door, asking if they could do surveillance from our parents house. Brother explained he didn't have authority to do that....they were definitely like descriptions of the Men in Black. My girlfriends and I had noticed their car sitting down the road a bit in the dark. When it came down the street towards us, we immediately went into the house. Their visit was shortly after that. My parents home was one block away from the EXACT dividing line for the watershed here - one side of the road, the water goes west. East side of the road flows east. The geological location - the multiple sightings and reports of others seeing the craft over the lake - the significance of the watershed lends credence to the idea that it really was someone checking us out or checking out the water situation or both. I've had multiple sightings of many kinds of aircraft in my life - aviation background owing to parents - and some sightings I had, I came to recognize as close-up views of new technology being shown somehow...probably testing equipment over snow-covered flat farmlands near where I was taking an early morning drive once ...again near the lake to the East. Different sighting entirely. Already reported to UFO researchers in my state. Other diverse experiences with this kind of contact throughout my life, really - many forms.