Number of unexploded ordnance disposal cases in Japan FY 2012-2021
During World War II, approximately 200 thousand tons of explosives fell on Okinawa, five percent of which are thought to have not exploded. Although the Self Defense Forces disposed of more than two thousand tons of unexploded ordnance since the U.S. handed over the islands back to Japan, Okinawa Prefecture estimated that there are still around 1.92 thousand tons left. Over 90 percent of the explosives are discovered due to public work projects.