LIndenhurst, Long Island New York -- Triangular Craft

My mother was giving me a ride home from work and we were on Hoffman Avenue headed home and our attention was grabbed by slowing cars ahead of us. We pulled over and looked up and there was a black, triangular carft above us, hovering...not moving, just hanging there in the sky.
 No one else stopped, so we left and went to our home. Once we got to the front steps, my mother pointed up to the sky and we saw about 4-5 more of the triangular black craft flying over what we believe was our locanl beach area (Venetian SHores Beach). They were flying like nothing we've ever seen, smooth and all over the place, looking like they were just taking everything in.
 Our neighbor who witnessed this with us was so disturbed she called our local police dept., where she was told that it was the Long Island Railroad conducting tests. I'm sorry it's so late reporting...but I haven't been able to talk about it really and even my mother and I never discuss it!!