On Friday, Japanese police arrested a man who had taken refuge in a building after reportedly using a gun and knife to kill four people, including two police officers.
The elderly woman who was found injured at the scene and later pronounced dead was the fourth casualty overnight, according to police, who apprehended the man outside a farm close to the city of Nakano in the Nagano area.
Two police officers and a second woman were earlier identified as having died in the assault.
The 31-year-old suspect was apprehended at around 4:30am (1930 GMT) on Thursday, according to the police, who subsequently confirmed that he had been formally arrested on suspicion of murder using a possible hunting rifle.
Japan, which has some of the toughest gun restrictions in the world and a low murder rate, saw a rare occurrence of violent crime during the rampage in a rural section of the western region.
Although some local media outlets said the suspect is the son of the speaker of Nakano’s municipal assembly, no motive has yet been established for the crimes, and neither has the suspect been officially named.
“We pray for the souls of the departed and express our profound sympathies to the grieving families,” said top government spokesman Hirokazu Matsuno to reporters.
According to the statement, police are looking into the event to learn the complete circumstances surrounding it, including how the crime began and its setting.