The US Navy has warned Japan that a small amount of radiation may have leaked from an American nuclear submarine during its recent visits to two southern ports. The US said the amount of radioactivity was negligible, but the news could cause a stir in Japan, where both the US military presence and its nuclear vessels are controversial.
Japan's Foreign Ministry said the US Navy told it that the nuclear-powered USS Houston might have leaked radiation during port calls in the southern Japanese ports of Sasebo and Okinawa in March and April. Sasebo city official Akihiro Yoshida said government monitoring during the submarine's calls showed no abnormal increase of radioactivity in the area's waters. "Still, we are rather concerned," Yoshida said.