With no one dead, one can safely conclude with a very reasonable margin of error that this is not an example of roleblocking. If mafia were roleblocked, the blocker would say who they blocked and it would nail the mafia right away. The only other explanation I can think of is cults.

http://www.mafiascum.net/wiki/index.php?title=Cult

I think that the lack of kills could be due to the idea of mafia not killing, but forcibly converting townies to scum. I'm asking the veterans here if they've encountered anything like this before, and if in that circumstance it was not a cult. Please contribute to the discussion here.