Japanese authorities are expanding partnerships between police and private businesses to prevent terror attacks by lone offenders who radicalize in isolation. The efforts draw lessons from the July 2022 fatal shooting of former Prime Minister Shinzo Abe. The focus is on detecting early warning signs in communities and online.
In the July 2022 fatal shooting of former Prime Minister Shinzo Abe, suspect Tetsuya Yamagami, 45, now indicted on murder and other charges, built his homemade gun at home without anyone noticing. Japanese authorities are expanding partnerships to detect early warning signs in local communities or online and stop such acts before they happen.
Help from the real estate industry illustrates these efforts. On Sept. 25, Kaoru Sakuma, head of security at the Metropolitan Police Department’s Takenotsuka Station in Tokyo’s Adachi Ward, visited a local real estate company, urging: “If you notice anything suspicious — such as the smell of gunpowder or metallic noises — please contact us immediately.” The MPD signed an agreement in May with three real estate associations to share information on suspicious activity in managed properties. Since then, officers from Takenotsuka Station have visited around 20 firms in the ward. Yamagami allegedly made firearms and explosives at his home and a rented garage; a neighbor recalled hearing “sawing sounds,” but no report was made. Authorities have added five chemical items, including sulfur used for gunpowder by Yamagami, to their monitoring list, requesting reports on unusual purchases.
Police are also bolstering ties with social media firms. Ahead of the July Upper House election, the National Police Agency asked the Japan branch of X Corp., formerly Twitter, for cooperation, providing coded terms like “56-su” (pronounced “korosu,” meaning “to kill”) to identify threats to political candidates and high-profile individuals. X responded to requests for user information within hours; one man who posted, “If [Kishida] comes [to campaign], he might not make it out alive,” was identified and warned, referring to former Prime Minister Fumio Kishida. During the month leading to election day, the agency found 889 dangerous posts on X and other platforms. An X spokesperson said the company “will respond [to police’s request] appropriately while respecting freedom of speech and expression.”
Online marketplace Mercari, Inc. and LY Corp., operator of Yahoo! Japan and Line, received police input and banned sales of empty shell casings for homemade bullets and Chinese-made toy guns capable of firing live rounds from July onward.
In April last year, police nationwide established a system to consolidate pre-incident information from investigations or patrols into security departments. In April this year, the MPD created a new section in its Public Security Division as a command center for lone-offender countermeasures. The National Police Agency is studying artificial intelligence to detect dangerous social media posts.
“Maintaining a balance between public safety and the protection of freedom and human rights is essential,” said Mitsuru Fukuda, a professor of crisis management at Nihon University. “The key challenge will be how to create an environment in which ordinary citizens feel comfortable reporting to or consulting authorities when they sense potential danger.”