Those people who learned the skills were called Ninja .
stories related to Ninjas are so popular that everyone might already have known that the origin of the Ninja and Ninjutsu are from Kouga ( current Shiga prefecture ) and Iga ( current Mie prefecture ) area .
Those people who learned the skills were called Ninjas .
stories related to Ninjas are so popular that everyone might already have known that the origin of the Ninja and Ninjutsu are from Kouga ( current Shiga prefecture ) and Iga ( current Mie prefecture ) area .