What is the maximum wanted level in Assassin's Creed 4?

I've been playing Assassin's Creed 4 : Black Flag for a while now and the thought just hit me, what is the highest wanted level on the game? I'm aware that when you raid a ship your wanted level goes up if you choose not to lower it, but I was just wondering what the max level is, and what kind of hunters are chasing you by that point.