The suspect was arrested after barricading himself in a building in a 12-hour standoff with police.
A 31-year-old man has been arrested in rural Japan after four people were killed in a rare gun-and-knife attack that saw police clash for 12 hours.
The suspect was taken into custody on suspicion of murder after barricading himself at his father’s house near the town of Nakano, northwest of the capital Tokyo, at about 4:30 am (7:30 GMT) on Friday.
The attack began on Thursday afternoon when a local man working on a farm saw a woman “running off the road shouting ‘help me’,” he told national broadcaster NHK.
“Behind her was a man in camouflage clothing and with a large knife, who stabbed her in the back,” the 72-year-old witness added.
The suspect is accused of shooting two police officers who arrived on the scene after the witness called the emergency services.
The two officers, who were reportedly shot in their car, and the woman were taken to hospital where they were pronounced dead within hours.
Another elderly woman also died after an apparent seizure. She had been lying on the floor outside the house since Thursday afternoon and the police had not been able to reach her, the media said.
The rampage in a rural area in the Western Region was a rare example of violent crime in Japan, which has a low homicide rate and some of the strictest gun laws in the world.
No motive for the killings has yet emerged, nor has the suspect been formally identified, although several local media reported that he is the son of Nakano Town Assembly Chairman.
“We pray for the souls of the deceased and extend our sincere condolences to the bereaved,” government spokesman Hirokazu Matsuno told reporters.
“Police are investigating to get the whole picture of the incident, including how the crime developed and its background.”
Few other details were known about the attack, including the suspect’s motive.
The Nagano Prefectural Police will hold a press conference later on Friday.
Japan was reeling last July when former Prime Minister Shinzo Abe was shot while campaigning.
Last month, a man was arrested for allegedly throwing a “smoke bomb” at Prime Minister Fumio Kishida while campaigning in the western city of Wakayama.
Kishida was unharmed and a man arrested at the scene will undergo a three-month psychiatric evaluation, a regional court said this week.