Tetsuya Yamagami, who killed former Japan Prime Minister Shinzo Abe on Tuesday pleaded guilty to the charges after three years of committing the crime, Kyodo News reported.
45-year-old Yamagami shot dead Abe while the latter was delivering a speech in July 2022.
"Everything is true," he said in court.
Yamagami was taken into custody right after he shot former Prime Minister Abe with a homemade firearm near a train station in Nara, western Japan. He subsequently underwent a mental health assessment that lasted nearly six months, after which prosecutors concluded that he was mentally competent to face trial.
Photos and videos of the shooting show the gunman was able to approach Abe from behind, while security guards were focused toward the front.
Motives behind Abe's assassination
According to reports, the suspect told police that he had initially planned to attack former Prime Minister Abe a day earlier during a speech in a different city. He said he dropped the idea because attendees were required to have their bags inspected at the venue.
Investigators and media sources say he later confessed that his motive for killing Abe stemmed from alleged ties between the former leader and a religious organization he despised.
Yamagami, was said to be angry because his mother’s substantial donations to the Unification Church had left their family in financial ruin.
PM Modi among attendees of Abe's state funeral
India had announced a one-day national mourning as a mark of respect for Abe. Prime Minister Narendra Modi also visited Japan to attend the state funeral of Shinzo Abe.
"I am travelling to Tokyo tonight to participate in the State Funeral of former PM Shinzo Abe, a dear friend and a great champion of India-Japan friendship," Modi tweeted hours before departing for Tokyo.
"I will be conveying heartfelt condolences to Prime Minister Kishida and Mrs Abe on behalf of all Indians. We will continue working to further strengthen India-Japan relations as envisioned by Abe San. @kishida230," he said.