Tokyo police raided two trading companies on Friday suspected of illegally exporting equipment to North Korea that could be used to create biological weapons, a news report said.
The companies allegedly exported freeze dryers that could be used to cultivate germs or other pathogens for possible weapons, Kyodo News reported, citing police.
The companies are suspected of shipping the equipment to North Korea through Taiwan in September 2002, Kyodo said.
The trading companies are suspected of violating the Foreign Exchange and Foreign Trade Control Law, which obliges exporters of such devices to apply for government permission, Kyodo reported.
Police officials were not immediately available for comment.
Late last month, police raided the headquarters of Yamaha Motor Co. on suspicion it illegally exported to China remote-controlled helicopters that could be diverted to military use.
The motorcycle and engine producer has accused of selling restricted materials without receiving approval.