Is my security camera going bad or is someone distorting it?

I have a home security camera system. It is wired, weather proof, and has night vision. The wiring is mounted along the side of my home and I made sure to set it in the camera's view so there is no way for anyone to tamper with it without being caught on camera. My question is... is it possible for someone to distort or cause an interference with my camera from a distance and without being near the camera's wiring? My camera has been showing some interference, but this only happens at night and I have been having a lot of problems with my next door neighbor which is why I installed the cameras to begin with. Could they being doing this, or is my camera possibly going bad?