Police officers among four killed in gun and knife attack in Japan
Japanese police have detained a man who barricaded himself in a building after allegedly killing four people including two police officers in a gun and knife attack.
The suspect was arrested outside a farm near the city of Nakano in Nagano region early Friday morning.
It was a rare instance of violent crime in Japan, which has a low murder rate and some of the world's toughest gun laws.
The suspect has been identified by local media as the son of politician Masamichi Aoki, the speaker of the Nakano city assembly.
He allegedly stabbed his victims with a large knife, before using a hunting rifle to shoot two policemen who responded to emergency calls.
The man then hid inside his parents' house. His mother and another woman managed to escape the property on Thursday night.
Authorities had urged people to stay indoors in the semi-rural area of central Japan after the rampage started on Thursday afternoon.
The slain officers were identified as Yoshiki Tamai, 46, and Takuo Ikeuchi, 61.
A local woman named Yukie Murakami, 66, was identified as one of the other victims.
A witness told the NHK public broadcaster he had been working at a farm nearby when "a woman came running from the road saying, 'help me', and she fell down".
"Behind her came a man wearing camouflage and carrying a large knife, who stabbed her in the back," the 72-year-old witness said.
He said he called emergency services while neighbours tried to resuscitate Ms Murakami.
NHK, citing police, said the attacker then fired what appeared to be a shotgun at police officers who arrived at the scene.
The officers were inside a patrol car and the attacker placed the weapon against a window of the vehicle and fired twice, NHK reported.
There was no known motive for the attack.
Japan was left reeling in July last year when former prime minister Shinzo Abe was shot dead in broad daylight with an apparently homemade gun.
Mr Abe's accused assassin, Tetsuya Yamagami, reportedly targeted the politician over his links to the Unification Church.
And last month, a man was arrested for allegedly hurling a pipe bomb-like explosive towards Prime Minister Fumio Kishida as he campaigned in the western city of Wakayama.
Video showed the moment an explosive device landed within a few feet of Mr Kishida, prompting a quick response from his security detail, who whisked him away and leapt on the suspect.
A group of fishermen were hailed as heroes after they tackled the suspect.
The PM was unharmed and the man arrested on the scene will undergo a three-month psychiatric examination, a regional court said this week.
The suspect has reportedly remained tight-lipped about his motive for that failed attack.
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