The Japan Coast Guard will bulletproof the wheelhouses of its patrol boats after two apparently North Korean spy vessels intruded into Japanese territorial waters in March 1999, it was learned Tuesday.
The Maritime Self-Defense Force dispatched destroyers to pursue the mystery ships on March 23 but abandoned the chase some 24 hours later when the vessels left the geographic boundary of Japan's Air Defense Identification Zone.
The ships, which bore the names of Japanese fishing boats, were equipped with a number of antennas and no fishing equipment was visible on their decks, the Defense Agency said at the time. Although they were last seen fleeing toward North Korea, Pyongyang later denied any involvement.
Sources close to the matter said the coast guard patrol boats are being fitted with bulletproof steel plates to protect crew members and make the boats more effective in the event of future encounters with suspicious ships.