Police officials say the suspect arrested after a stabbing and shooting attack that left four people dead in central Japan has admitted to killing a police officer.

31-year-old Aoki Masanori, the son of a city assembly chief in Nagano Prefecture, was arrested on suspicion of killing the officer.

Police say Aoki told them that he shot and killed the victim.

Police suspect Aoki also attacked his neighbor Murakami Yukie and another elderly woman with a knife, then shot at police officers Tamai Yoshiki and Ikeuchi Takuo, apparently with a hunting rifle.