Whatever that announcement is, it is a lie.
But there's no way for me to prove it since I have no intention of revealing my awesome role to the public, and it's an NOC game.
So believe what you want. But the best case scenario for all of us is for you to not lynch me, since that announcement is obviously a lie. Consider the following:
Why would a village announcer announce someone as being mafia without proof? There's no real reason to: either they hit correctly (which is extremely unlikely) or they hit incorrectly, which gets a villager lynched.
Why would a mafia announcer announce someone as being mafia without proof?
This is much more likely in my mind, because the mafia knows who is in the mafia and can get a villager lynched.
Why am I a better target then any of our previous scum suspects? You guys can probably answer this better then me, given that you've been playing mafia longer then I have and you have a better read on people's playstyles.