The top bureaucrat of the Japanese police offered Thursday to step down to take responsibility for the assassination of former Prime Minister Shinzo Abe.

Itaru Nakamura, commissioner general of the National Police Agency, expressed his intention at a press conference where the agency announced the results of its investigation into the police's failure to protect Abe when he was fatally shot while delivering a stump speech in the western city of Nara last month.

The agency concluded that there was a "high likelihood that (the attack) could have been prevented" had the police planned to place officers in the area behind the former prime minister appropriately.

Itaru Nakamura, commissioner general of the National Police Agency, holds a press conference at the agency in Tokyo on Aug. 25, 2022. (Kyodo)

"As we advance new security arrangements, it is a matter of course to go at it with a new lineup of people," Nakamura said.

The National Public Safety Commission punished Tomoaki Onizuka, head of the Nara prefectural police, with a 10 percent pay cut for three months for failing to craft an appropriate protection plan for Abe. He also offered to step down the same day.

The prefectural police also announced disciplinary measures within their own ranks, including against a superintendent in its security division.

In announcing the results of its review of the case, the agency said a sudden change in the placement of police officers just before Abe's speech created "space" in the area behind him that was left unguarded, enabling the attacker to approach and fire two shots from behind.

When Abe gave the speech on July 8, ahead of an upper house election, one officer dispatched from the Tokyo metropolitan police force and several local police officers were in his immediate vicinity. However, none were able to stop the assailant before he shot the former prime minister from behind, according to the agency.

Abe was standing in a small area surrounded by guardrails. Just before he was about to commence his speech, one of the prefectural police officers, who had been standing outside the guardrails and watching Abe's back, moved inside and turned to face the audience without notifying the other officers or the team leader, who was not in the enclosed area, according to the agency.

As part of efforts to beef up the protection of VIPs, the agency said it will set up a new section within the Security Bureau while doubling the number of officers who serve as bodyguards for VIPs at the Metropolitan Police Department and acquiring systems aimed at detecting suspicious figures by harnessing the power of artificial intelligence.

The NPA also revised its rules for VIP protection, enabling it to get involved more in such activity, such as by screening in advance protection plans made by local police forces.

Nakamura became agency commissioner general in September last year. He had previously served as a secretary to the chief Cabinet secretary between 2009 and 2015, including when former Prime Minister Yoshihide Suga was Abe's chief Cabinet secretary.

Abe's assailant, Tetsuya Yamagami, was arrested on the spot and sent to prosecutors on suspicion of murder. The court later approved prosecutors' request to keep him in custody until Nov. 29 for psychiatric evaluation to see if he can be held criminally responsible.

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