South Korea, the United States and Japan on Monday began a combined naval exercise against North Korea's growing submarine threats, Seoul's defense ministry announced. 
The three-day training was kicked off in the waters between South Korea and Japan near Jeju Island, involving an Aegis system-equipped guided missile destroyer, several other warships and military choppers, according to the Ministry of National Defense. 
It's aimed at securing an "effective response" by the three countries to the North's submarine threats, especially as it's developing submarine-launched ballistic missiles (SLBMs), it added, South Korea's Navy has dispatched the 4,500-ton Kang Gam Chan destroyer and a Lynx helicopter, with the US sending the USS McCampbell, a destroyer armed with the Aegis ballistic missile defense system, an MH-60 anti-submarine chopper and a P-3 Orion patrol plane. Japan's copter-carrying destroyer, the Sawagiri, also joined the drill, state news agency (Yonhap) reported. 
"The anti-submarine training of the three countries is the first since it was discussed in their Defense Trilateral Talks (DTT) in December," the ministry said, adding it represents their strong determination against North Korea's nuclear and missile threats. 
The move comes amid reports that the North is apparently preparing for another nuclear test and more missile launches. 

Source: QNA