A 22-year-old former Self-Defense Forces member was served a fresh arrest warrant Wednesday over the murder and robbery of an officer at a police box in the city of Toyama in June.
Keita Shimazu is alleged to have fatally stabbed Kenichi Inaizumi, the 46-year-old head of the police box, before shooting and killing 68-year-old Shinichi Nakamura, a security guard at a nearby elementary school, with the gun he took from the police officer.
The suspect has more or less admitted to the charges, investigators said.
In the June 26 attack, Shimazu is suspected of having stabbed Inaizumi in the abdomen several times before stealing his handgun and shooting Nakamura near the front gate of the school, according to the police.
He had already been arrested in connection with the shooting of the security guard.
Shimazu was shot by two police officers in the incident. He was released from hospital Wednesday.
Immediately before the incident, Shimazu had a quarrel with a manager of a restaurant where he worked part time, according to the investigators.
Police searched his home and found more than a dozen toy guns and books on how to commit murder.
Shimazu served as a member of the Ground Self-Defense Force for two years through March 2017.
