During the Vietnam War, US military bases in Japan, especially those in the Okinawa Prefecture, were used as important strategic and logistic bases. In 1970, the Koza riot occurred against the US military presence on Okinawa. The USAF strategic bombers were deployed in the bases on Okinawa, which were still administered by the U.S. government. Before the 1972 reversion of the island to Japanese administration, it has been speculated but never confirmed that up to 1,200 nuclear weapons may have been stored at Kadena Air Base on Okinawa during the 1960s.