 U.S. Ambassador to Japan Rahm Emanuel expressed regret about the incidents, but did not apologize. Okinawa hosts about 70 percent of U.S. military bases in Japan on less than 1 percent of its land, and sex crimes involving U.S. servicemen have angered locals for decades. Japan's government doesn't publish complete statistics, but Okinawan women's history researcher Harumi Miyagi keeps a tally of known cases.