The next day, I spoke to a historian and finally told her what we saw. She just stared at me and said. The area you saw it running to is an old church. The area it ran from was an old burial ground. The way you described it is how they used to bury the dead.
I have no logical explanation for what I saw. I know it wasn't someone screwing with me. I think sometimes, St Augustine likes to share some of her mysteries and spirits.