Japan has been leasing land on another of the five disputed Senkaku Islands near Taiwan in a contract that runs through 2012, in addition to the three others recently reported to be subject to similar leases with the government, officials said Wednesday.

"When Okinawa was reverted (to Japan from the United States) in 1972, privately owned land on Kuba Island was leased (by the Japanese government) so that the island could be used as a firing range of the U.S. military, and that contract has since been renewed," an official of the Defense Facilities Administration Agency said, adding that he believes the matter was made public at that time.

Kuba is one of the five uninhabited East China Sea islands, known in Japan as the Senkaku chain, that were returned to Japan by the U.S. along with Okinawa in 1972.