I observed large object over Long Island Sound near Charles Island in Milford, CT. I went out to make sure our cars were locked because there have been a number of car break ins lately. I thought it was a blimp at first but it seemed to be too large. I then went to the beach end at the end of my street too see what it was. I then noticed flashing lights of different colors in sequence near what seemed to be the middle of the object. The object seemed to be stationary. I then noticed what seemed to be helicopters coming from the Stratford/Devon area towards the object. Then over head came three low flying helicopters at rapid speed. At first I thought there must be some explanation or that it was in fact a blimp (however large) until the helicopters showed up. I then observed for about a half hour. As soon as the helicopters came near the object it disappeared. I didn't see any trails or anything. Just one minute it was there and then it wasn't. I did not call authorities because I didn't want to seem paranoid or crazy. I watched the helicopters comb the area for about a half hour. Three broke off and came closer to my location and I thought I could see something like a parachute or something hanging below one of them. They then reversed direction and headed towards Stratford/Devon CT. One by one they seemed to land, except one. This one seemed to patrol the area. I then went home to tell my wife. I am still not quite sure what I witnessed but it was definitely strange. Sikorsky Aircraft is in Stratford and they sometimes test helicopters but never this late at night. We don't have any bases in this immediate area that I am aware of. The object seemed to be beyond Charles Island, which is small but not tiny and the object seemed to be much larger as it was farther away. When I first saw the object I wanted to go down to the beach end and see what the heck it was but then I got a whole lot more. My wife thinks I'm nuts and I don't have any video or witnesses. I kept looking around hoping someone would show up so I could have backup but no one did. I don't know as of yet if anyone else observed the object. As I am reporting this right away so it is still fresh. I wish to remain anonymous as to avoid and ridicule but I though you should know so at least you could look into it. Thank you.