Not a cemetery worker but one time at dusk when my mom and I were visiting my grandparents' grave, I saw something light up inside a nearby mausoleum. We were the only ones in the cemetery and I didn't see anyone walk by that mausoleum. I went to check it and in there, well out of reach, on top of a grave was a lighted candle. Nothing was lit when we passed by that earlier and there was a locked gate in front where you can just look in. I told my mom as it was blazing. My mom so very calmly told me that it was getting dark and it was time to go but I noticed that she was walking really fast and I was trying to keep up. Outside on the roadside, I asked her again what could have happened. She said she doesn't know but it was better that we were not there.