I found this case in/around the spring of 1967. With a lot of UFO activity around New England I was going to airports, police stations and any place where a UFO would be reported. So I went to a small airport that was located on a river in Haverhill, Massachusetts... Ray Fowler has this in his appendix 1 in his book "UFOS Interplanetary Visitors"
As the lead investigator and the one who found this case for Ray I will relate what happened.
I drove in to leave my card and ask the Airport operator, who I later found out was also the harbor master for the Haverhill, Massachusetts River: the upper Merrimack River that runs from Upper NH and into Newburyport Mass.
When I gave him my card, he opened up and walked me to his aircraft pad. Right there on this pad he told me a story that occurred around the 4/67 date.
Late at night he heard a whirring sound and saw some faint glow from a craft that was hovering over a pond he had on his property. At first he thought it was an aircraft in trouble. The glow was from a silvery object that had 2 silver saucers placed rim to rim with a transparent dome on the front.
As he watched it for about 5 minutes, he saw 2 figures. These figures had antennae on their helmets (heads) and they turned and looked at him. The yard light dimmed when the object hovered and he remembered that there was a sulfur smell in the air.
As the object took off the smell went away and the yard light came back up and there were no noticeable fluids on the ground. The man was in the Navy, and said that he had heard of sightings, but never believed them until he saw this.
During this time frame there were numerous sightings of a UFO in the area with reports coming in every night. When I reported this to Ray Fowler he asked me to set up a date when He, Walter Webb, and I could come up and do a further investigation.
So I set up the appointment, and all 3 of us did a 3-4 hour investigation of this near landing site. It is all documented...
source and references:
"UFOS Interplanetary Visitors" by Ray Fowler
Archived UFO Case Files
UFO Casebook Home Page