This question already has an answer here:
When walking around at night, I feel like some other people walking around may be worried. Everyone who knows me knows there is no need for worry, but my stature could make me look threatening to a stranger at night. I do not think everybody is scared, but people walking alone or that are otherwise vulnerable, so to speak, probably would be. I do not think I am special in this regard though.
That being said, what is proper etiquette in this situation? For example, yelling "Do not be alarmed stranger. I am not an axe murder" probably is not it.
The biggest problem is if we are headed in the same direction and I am behind them, since then it can appear that I am following them.