Police investigate near the home of Masamichi Aoki, chairman of the Nakano city assembly (Video footage by Takahiro Kumakura)

NAKANO, Nagano Prefecture—The son of the Nakano city assembly chairman was arrested on May 26 on suspicion of murder following a shooting and stabbing rampage that killed two women and two police officers.

Nagano prefectural police detained Masanori Aoki, 31, early in the morning after he was holed up at the home of his father, Masamichi Aoki, chairman of the Nakano city assembly.

The son is accused of murdering a 61-year-old police officer the previous day. Police are continuing to investigate Aoki’s apparent role in the fatal shooting of another police officer, as well as the deaths of two elderly women.

Nagano police said they received an emergency call at 4:25 p.m. on May 25 about a woman being stabbed by a man.

Police believe that Aoki, armed with a hunting rifle, shot the two officers after they arrived at the scene.

He then holed up in his family home.

His mother fled the home around 8:30 p.m., and his aunt escaped after midnight. They were taken into police protection.

That left Aoki alone in the home.

He was detained around 4:30 a.m. when he surrendered to police, and was taken to the Nakano Police Station for questioning.

Aoki emerged from the house with his hands up, police said at a May 26 news conference.

Police identified the dead officers as Yoshiki Tamai, a 46-year-old inspector, and Takuo Ikeuchi, a 61-year-old sergeant. 

They were not wearing bullet-proof vests when they responded to the emergecy call, the prefectural police chief said.

Yukie Murakami, 66, was stabbed to death in the area. The body of Yasuko Takeuchi, 70, was found near the Aoki home after the suspect was detained.

In Tokyo on May 26, Koichi Tani, chairman of the National Public Safety Commission, said at a news conference that Aoki had licenses to own hunting and air rifles.

Masamichi Aoki resigned from the Nakano city assembly on the same day.