S.Korea, U.S., Japan Stage Naval Drills

South Korea, the U.S. and Japan kicked off two days of maritime exercises in international waters south off Jeju Island on Monday that include the nuclear-powered aircraft carrier USS Nimitz. They are already the second three-way drills since last September.

From South Korea, the Aegis destroyer Yulgok Yi Yi, destroyers Choe Yeong and Dae Jo-yeong and the combat support ship Soyang are taking part. 

From the U.S., the Aegis destroyer USS Decatur and guided-missile destroyer USS Wayne E. Meyer are joining and from Japan the destroyer Umigiri. 

"Anti-submarine drills were conducted to improve the three countries' response capabilities against the growing underwater threat from North Korea including its submarine-launched ballistic missiles," the Defense Ministry here said.

For targets they used small dummies that send out sonar signals to practice responding to a new unmanned nuclear attack craft that the North tested recently, a military officer here said.