The Village of Konoha is protected by a special sensory barrier that spans the entire area, from underground to the skies. This system is managed by the Sensory Unit, led by the Yamanaka Clan, which is responsible for monitoring the chakra of everyone within Konoha, as well as those entering and exiting through the Main Gate. If any foreign chakra enters without authorization, the Sensory Unit will immediately detect it and report it as an infiltration attempt.

Despite Konoha being safeguarded by a barrier jutsu formula, Uchiha Itachi was still able to infiltrate the village with remarkable ease.

Here is how Itachi managed to enter the Village of Konoha without being detected.

1. How Itachi Infiltrated the Village of Konoha

As the sole perpetrator of the Uchiha Clan massacre in Konoha and a name listed in the S-rank Bingo Book of fugitives, Itachi’s chakra should have been identified and closely monitored by the Yamanaka Clan’s Sensory Unit. If Itachi attempted to infiltrate Konoha again, his presence should have been immediately detected.

However, impressively, Itachi managed to enter Konoha undetected by the Sensory Unit. He even brought Kisame along to roam and relax within the village. As a former leader of the Black Ops Anbu, Itachi was privy to a secret password granted by the Third Hokage, Hiruzen Sarutobi, which allowed him to bypass Konoha’s barrier jutsu undetected.

After the Uchiha Clan massacre, Itachi and the Third Hokage held a secret meeting. During this meeting, Hiruzen promised not to change the village’s barrier jutsu password as a sign of respect for Itachi’s role in maintaining peace in Konoha and preventing a civil war between the Uchiha Clan and the village.

However, due to his actions, Itachi had to bear a significant burden: he was branded a criminal and placed in the Bingo Book with a bounty on his head, dead or alive. He also had to live with the stigma of annihilating the entire Uchiha Clan, sparing only his younger brother, Sasuke Uchiha.

Because he knew the secret password, Itachi could easily enter Konoha and even bring Kisame along without being detected by the Yamanaka Clan’s Sensory Unit. In fact, apart from Itachi, there were a few elite figures in the village who also knew the password to bypass Konoha’s barrier jutsu.