Blueprints to create a handgun with a 3-D printer were downloaded through the Internet to at least eight personal computers in Japan, a US political organisation has said in an interview with The Yomiuri Shimbun.
Yoshitomo Imura, a university employee who was arrested Thursday on suspicion of possessing plastic guns, is suspected to have downloaded them from the site of Defence Distributed, a nonprofit organisation that offers original gun designs online.
Defence Distributed founder Cody Wilson, 26, said the organisation released the blueprints on its website in May 2013.
The group posted the blueprints on the website for only two days as it received a request from the US government to delete them. During those two days, however, the blueprints were downloaded more than 100,000 times in over 40 countries, he said.
By checking the records of IP addresses, the group confirmed that the blueprints were downloaded to eight personal computers in Japan, according to Wilson.
Wilson said it's highly likely that many more individuals in Japan obtained the blueprints, as the organisation confirmed only some of the IP addresses that contacted the website and the blueprints continued to spread through other websites even after the organisation deleted them from its own site.
According to sources close to investigators, Imura said he obtained the blueprints from a US website.
Before Imura was arrested, he posted comments on Twitter and other social media sites, such as, "I will spread the blueprints for a 3-D printed gun that everyone can easily create." In fact, he did also release the blueprints on the Internet.
Wilson said he saw the guns that were seized from Imura's home on the news. He said he believes one of the guns was made using blueprints provided by Defence Distributed. Other guns seemed to be created based on the blueprints, but are likely Imura's original design as they were considerably modified, Wilson said.
Wilson's remarks suggest there could be others in Japan who have created or will create 3-D printed guns.
However, it is difficult to track down and specify access and download records in connection with foreign websites, observers said.
"As the suspect himself posted the guns he created on the Internet, the case was brought to public attention. So it was just an unexpected happening," lawyer Hisamichi Okamura said. "I can't imagine how far the blueprints have spread throughout the nation."
'I can create bullets'
Yoshitomo Imura, who was arrested on suspicion of possessing plastic 3-D printed guns, intended to create guns that can fire bullets, he has been quoted as saying during a police investigation.
The Kanagawa prefectural police did not confirm whether there were traces indicating that bullets had actually been shot from the guns, but quoted him as saying: "I can also create real bullets at any time if I want to do so. I have confidence in my skill."
Before Imura was arrested, he reportedly said during questioning by police on a voluntary basis, "I actually made that gun, but I didn't think it was illegal."
But the police believe that he possessed the guns in full knowledge of guns' potential to kill or injure.
According to investigators, since Imura's interest in handguns began when he was a primary school student, he is believed to have collected information on various kinds of guns and their structures from the Internet.