Everything We Know About the Knife Attack in Japan That Killed At Least 19

At around 02:00 on Tuesday, Satoshi Uematsu put a hammer through the window of his old workplace. Prowling around the first floor, he opened a bag filled with knives. The 26-year-old––apparently motivated by a desire to eradicate the disabled––then started slashing people's throats. In the end, he killed at least 19 and seriously injured about 20 more at a residential facility for the handicapped located an hour outside of Tokyo.

After attacking nearly a third of the center's residents at his leisure, Uetmatsu drove to the Sagamihara police station and confessed to one of the deadliest crimes to take place in Japan since World War II. The country has one of the lowest homicide rates in the world, according to the United Nations, and some reports are calling the slashings the biggest mass murder to ever happen there. Regardless of its scale, the fact that it happened at all is the result of disturbing negligence by Japanese officials who failed to act despite repeated warnings.

Back in February, Uetmatsu delivered a letter to a Japanese politician asking for permission to mercy kill the handicapped. "I dream of a world where the disabled can die in peace," it read. "I will carry out the plan without hurting the staffers, and I will turn myself in after I kill the disabled."

The letter proposed an elaborate plan involving the killing of 470 disabled people as part of a "revolution." What he wanted from the politician was a guarantee that he could get off on insanity grounds and be given $5 million and plastic surgery to start a new life afterward.

Days later, he was questioned by police for handing out fliers near the facility that contained similar comments, and he was eventually committed to a mental hospital, where he was diagnosed as paranoid and dependent on weed. Despite working at a facility that cared for disabled people, and harboring a stated desire to murder them, Uematsu reportedly first got in trouble with his boss over tattoos on his chest and back.

Yuji Kuroiwa, the governor of the Kanagawa Prefecture, has apologized for not acting in advance, according to the Associated Press. The nine men and ten women who died ranged in age from 18 to 70.

Uematsu's attack lasted about 40 minutes, and it's likely he would have claimed many more victims if Japan's gun-control laws had been more lax. It's completely illegal to own a handgun in the country, and to get a shotgun or rifle is a longwinded process (even members of the notorious Yakuza gang rarely carry firearms.) In 2014, there were only six gun-related deaths in the entire country, and in 2015, there were only eight crimes in which guns were fired. As such, knives are the weapons of choice for the country's most infamous crimes. In 2001, a former janitor stabbed eight children to death at their school. In 2008, a man murdered eight people at a shopping center with a dagger.

Meanwhile, in Japan, confessions are extremely common. Police aren't allowed to conduct wiretaps or undercover operations, and the legal system doesn't allow for plea bargains, so authorities are forced to rely on a cultural pressure to unburden oneself after wrongdoing. Perhaps because of this, the country has a 99 percent conviction rate. Uematsu reportedly told police in no uncertain terms, "I did it."

If Uematsu made troubling but consistent remarks to politicians and co-workers, his Twitter account reveals that he was fixated on a number of things he believed were afflicting his homeland, like AIDS and radiation poisoning. On July 23, he commented on a teen gunman killing nine people in Munich, Germany, saying, "it would have been fun if it was a toy."

His final missive came just after an employee of the facility called the police Monday morning. "May there be peace in our world," it read. "Beautiful Japan!!!!!!"

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