Anchor: South Korea, the U.S. and Japan conducted a two-day trilateral naval exercise in international waters off the Korean Peninsula. The three sides focused on stopping the transfers of weapons of mass destruction(WMDs) in open waters among other drills, mobilizing six warships, including a Nimitz class nuclear-powered aircraft carrier.
Kim Bum-soo has more. 

Report: South Korea's Aegis destroyer, ROKS Seoae Ryu Seong-ryong, and Japanese Maritime Self-Defense Force's JS Ariake joined USS Theodore Roosevelt for a two-day drill off the southern coast of Jeju island.

As fighter jets were landing on and taking off from the nuclear-powered aircraft carrier Friday, Rear Adm. Christopher Alexander told reporters that the naval training is aimed at improving the three sides' joint tactical proficiency. 

[Sound bite: Rear Adm. Christopher Alexander - Commander, Carrier Strike Group 9] 
"This is a routine operation. This is a routine exercise in international waters. While we are here, we are working on increasing our tactical proficiency. Specifically, we are working on undersea warfare exercises. We are working on maritime interdiction operations. We are working on search and rescue operations. We are working to better communicate and share data... All of which better prepare us for a crisis in the region or any contingency within the region." 

The commander of the carrier strike group called the training a routine operation. However, it is rare for the U.S. navy to allow media access to its strategic assets during an ongoing exercise. 

The three sides focused on improving their joint response against North Korean provocations, conducting anti-submarine drills, as well as a maritime interdiction exercise, aimed at stopping the transfers of weapons of mass destruction(WMDs) in international waters. 

The trilateral exercise is the latest of a series of joint drills which Seoul, Washington and Tokyo decided to regularize during their Camp David summit last year. 
Kim Bum-soo, KBS World Radio News.