The son of a city assembly chief in central Japan was arrested Friday as he surrendered to the police in the early hours following a stabbing and shooting attack that left a total of four people dead.

Masanori Aoki, 31, is investigated in connection with the death of two local women and the fatal shooting of two police officers in Nakano, Nagano Prefecture. He was quoted as telling the police that he killed the women "because I thought they said bad things about me" and the policemen over fears they would "shoot and kill me."

The suspect, the eldest son of Masamichi Aoki, speaker of the Nakano city assembly, is so far charged with murdering one of the two officers, toward whom he fired a hunting gun. He has admitted to the shooting.

A car (R) carrying a man who had barricaded himself in a house in Nakano, Nagano Prefecture, heads to the Nakano police station around 4:49 a.m. on May 26, 2023. (Kyodo)

The deadly attack that took place Thursday afternoon had gripped the area, with the suspect barricading himself in his home, where he lived with his parents, and prompting nearby residents to evacuate as he was feared at the time to possess a gun.

Following calls from the police to surrender, Masanori Aoki came outside after holing up for about 12 hours and was taken into custody at around 4:30 a.m. on Friday.

According to the police, the suspect has since 2015 held and renewed licenses for four firearms, including shotguns and air guns. One of them could have been used in the latest incident.

Gun ownership is strictly controlled in Japan. The police said that there had been no problem over issuing him the licenses.

A member of a local hunting club, Aoki is known to have gone to firing ranges and bought shotgun rounds.

Neighbors described him as "quiet" and said he did not leave the house often. He is believed to have been involved in operating a farm that supplied fruit to a gelato store his father had opened.

In his junior high school graduation yearbook, he wrote that he thought the "most important thing in this world is 'life.'" In the same piece, he also mentioned the importance of money and expressed concern he might become a member of the "working poor."

According to the police, Aoki is believed to have stabbed Yukie Murakami, a 66-year-old nearby resident, and then fired at the two police officers who arrived at the scene before barricading himself in the house.

The two policemen -- Yoshiki Tamai, 46, and Takuo Ikeuchi, 61 -- had not been wearing bulletproof vests at the time because they were called out for a reported stabbing, according to a senior police officer.

Another woman, Yasuko Takeuchi, 70, was also found collapsed near the Aoki family's house and was later confirmed dead. According to police, Murakami and Takeuchi would often go out walking together.

The police are investigating the relationship between the suspect and the two women, who both had stab wounds.

Through the early hours of the morning, the suspect's mother and aunt escaped the house. The 57-year-old assembly chief was confirmed safe after his son's surrender.

Masamichi Aoki submitted his resignation as a city assembly member on Friday, only citing "personal reasons."

The last time multiple police officers were killed in an incident in Japan dates back to 1990 in Okinawa Prefecture when two plain-clothes officers patrolling amid a gang war were targeted after being mistaken for gangsters, according to police sources.

Iwao Koyama, chief of the Nagano prefectural police, expressed condolences to the bereaved, adding that the death of the two officers was a matter of "great sorrow."

Photo taken from a Kyodo News helicopter on May 26, 2023, shows a house in which a man barricaded himself in the Nagano Prefecture city of Nakano, central Japan, after a stabbing and shooting incident a day before. Four people, including two police officers, died in the incident. (Kyodo) ==Kyodo

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