My UFO experience was back in 2001 - very shortly after 9/11 (a week or two afterwards, I think).
It was around 1:30 AM and I was on my way to work. I had my window down a bit and could hear the usual sounds of the night - insects chirping and the like. As I began crossing the Mauricetown bridge (crosses the Maurice River) I could hear the insects, frogs, etc.. but those normal sounds faded away as the bridge rose up over the river. Just as I approached the crest of the bridge I saw what appeared to be a cockpit light - as if someone turned on their interior light to read a map - roughly 150 yards north and a bit higher than the crest of the bridge. The object didn't move - it just held there above the river.
I suspect it was a helicopter, but there wasn't so much as a whisper of rotor noise - the night was completely silent save for the distant sounds of insects and frogs, and the noise made by my vehicle. The light was on for maybe 3 seconds and then complete darkness except for the area illuminated by my headlights.
For me the experience was just weird; nothing scary about it. I still find it difficult to believe a helicopter can be absolutely silent while hovering in the air. I wasn't more than 150 yards away, but I never would have known anything was nearby if it wasn't for the brief amount of time that the light was on. It was clearly a cockpit light. There were no other vehicles, and no boats on the river. The insects/frogs never ceased their nightly routines - an unlikely event had there been a typical helicopter hovering nearby.
I'm not sure why the government would have been surveilling that particular area; it isn't very populated, nor is it a major port area. The Maurice River does dump directly into the Delaware Bay and is a fairly good sized river but it doesn't have a ton of commercial significance. The river is mostly known for its eagles and other birds of prey... and recreational fishing.