Good question. I have yet to see any video or pictures of them. Granted, I’ve not been looking into this but for an hour or two a day since.
I just assume they were SS. There were pics of snipers on both roofs but this was all I could find in a quick search.
https://www.cbsnews.com/news/trump-rally-shooting-pennsylvania-gunman-snipers-location-maps/