SEOUL, Oct. 30 (Yonhap) -- The United States deployed an RC-135U reconnaissance plane to one of its air bases in Japan, an aviation tracker said Wednesday, a move seen as aimed at beefing up surveillance of North Korea. One RC-135U Combat Sent arrived at Kadena Air Base in Japan's Okinawa on Tuesday from Offutt Air Force base in Nebraska, Aircraft Spots said in a Twitter post. The U.S. air force is known to operate two RC-135Us, which collect and analyze electronic radar transmissions. The deployment came amid concern the North could conduct additional missile launches. A military source said that...