WTF Copter

So, I'm sitting at home this evening--minding my own business watching a little TV after dinner. I hear a helicopter fly by and it sounds kinda low. But that's not too strange. But after a few minutes, I realize that I can still hear it flying around.

So I step out onto my back porch and there he is--flying really low (~500 ft) and only about a block away. So I watch for a bit and realize he's flying in circles over a point that can't be more than a block away.

I stand there for 10 minutes and he just keeps circling. Then I see another helicopter flying slowly above at about 1,500 ft.

So I grab my camera and decide to snap some pictures. Somebody must be watching because he hovers directly over my house for about 15 seconds before continuing the circling.

That's the strangest thing I've seen in a while. As I write this, I can still hear him making his rounds.