JMSDF P-3C MPA and Asagiri-class Destroyer Detected a Submerged Submarine in Sea of Japan
 
The Japan Maritime Self-Defense Force (JMSDF) detected an unidentified submarine near Tsushima Island situated in the Korea Strait between the Japanese mainland and the Korean Peninsula.
The Japan Maritime Self-Defense Force (JMSDF) detected an unidentified submarine near Tsushima Island situated in the Korea Strait between the Japanese mainland and the Korean Peninsula.
 
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Naval Forces News - Japan
 
 
 
JMSDF P-3C MPA and Asagiri-class Destroyer Detected a Submerged Submarine in Sea of Japan
 
The Japan Maritime Self-Defense Force (JMSDF) detected an unidentified submarine near Tsushima Island situated in the Korea Strait between the Japanese mainland and the Korean Peninsula.
     
The Japan Maritime Self-Defense Force (JMSDF) detected an unidentified submarine near Tsushima Island situated in the Korea Strait between the Japanese mainland and the Korean Peninsula.
JMSDF P-3C Orion Maritime Patrol Aircraft. Picture: JMSDF
     
The Japanese Ministry of Defense issued the following statement:

On the morning of February 15th, the Maritime Self-Defense Force (MSDF)'s P-3C, patrol helicopter, and the destroyer Asagiri confirmed a submerged submarine in waters southeast of Tsushima (Nagasaki Prefecture) within the contiguous water zone, navigating in the southwest from the Sea of Japan toward the East China Sea.

Thereafter, MSDF confirmed that the submarine navigated in the southwest through the Tsushima Strait Eastern Channel.
     
The Japan Maritime Self-Defense Force (JMSDF) detected an unidentified submarine near Tsushima Island situated in the Korea Strait between the Japanese mainland and the Korean Peninsula.
JMSDF Asagiri destroyer (first ship of the class). Picture: JMSDF
     
Between 2013 and 2014 the JMSDF detected unidentified submarines in three sperate occasions in the contiguous zone of the southern area of Okinawa.

The contiguous zone is a band of water extending from the outer edge of the territorial sea to up to 24 nautical miles (44.4 km; 27.6 mi) from the baseline, within which a state can exert limited control for the purpose of preventing or punishing "infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory or territorial sea". This will typically be 12 nautical miles (22 km; 14 mi) wide, but could be more (if a state has chosen to claim a territorial sea of less than 12 nautical miles), or less, if it would otherwise overlap another state's contiguous zone.