Police say that the young Japanese man who went on a stabbing rampage on Tuesday at a facility for the mentally disabled where he had been fired, killing 19 people, had months earlier given a letter to Parliament outlining the bloody plan and saying all disabled people should be put to death.
When he was done, Satoshi Uematsu, 26, had left dead or injured nearly a third of the almost 150 patients at the facility in a matter of 40 minutes in the early Tuesday attack, the deadliest mass killing in Japan in decades, authorities said.
Twenty-five were wounded, 20 of them seriously.
Security camera footage played on TV news programmes showed a man driving up in a black car and carrying several knives to the Tsukui Yamayuri-en facility in Sagamihara, 50 kilometers (30 miles) west of Tokyo.
The man broke in by shattering a window at 2:10 am (local time), according to a prefectural health official, and then set about slashing the patients’ throats.
Details of how he did that, and if the victims were asleep or otherwise helpless, were not immediately known, although a letter he sent to Japan’s Parliament in February gave a peek into Uematsu’s dark turmoil.
He calmly turned himself in about two hours after the attack, police said.
Tsukui Yamayuri-en, which means mountain lily garden, was a facility Uematsu knew well, having worked there since 2012 until he was let go in February.
He knew the staffing would be down to just a handful in the wee hours of the morning, Japanese media reports said.
Not much is known yet about his background, but Uematsu once dreamed of becoming a teacher. In two group photos posted on his Facebook, he looks happy, smiling widely with other young men.
“It was so much fun today. Thank you, all. Now I am 23, but please be friends forever,” a 2013 post says.
But somewhere along the way, things went terribly awry. Uematsu began to tell people around him that disabled people needed to be killed.
In February, he tried to hand deliver a letter he wrote to Parliament’s lower house speaker demanding all disabled people be put to death through “a world that allows for mercy killing,” Kyodo news agency and TBS TV reported.
Uematsu boasted in the letter that he had the ability to kill 470 disabled people in what he called was “a revolution,” and outlined an attack on two facilities, after which he said he will turn himself in.
He also asked he be judged innocent on grounds of insanity, be given 500 million yen (USD 5 million) in aid and plastic surgery so he could lead a normal life afterward.
The letter was reprinted by Kyodo after the attack.