The small boat in the hold of the North Korean spy ship salvaged earlier this month from the East China Sea carried a global positioning system that may have stored records of its movements, the Japan Coast Guard said Friday.
Coast guard officials said they will investigate the system, which may have been made in Japan, after the ship is brought to shore. They suspect the boat had at one time navigated separately from the mother ship.
The discovery of the GPS came about while the coast guard was disposing of explosive devices found in the boat's steering compartment, the officials said.
GPS, which links satellites to computers and receivers for pinpointing positions on Earth, is widely used on vessels and aircraft as well as in car navigation systems.
The officials said they are still searching for the mother ship's GPS. The bridge, where the GPS was located, separated from the ship and broke into pieces when the vessel went down.
The ship also carried a Japanese-made radar. In light of that, as well as the discovery of a Japanese-made GPS aboard a North Korean midget sub that the South Korean navy sank in 1998, the coast guard officials said it is highly likely the GPS on the small boat was also made in Japan.
The ship sank after a shootout with Japanese patrol boats last Dec. 22. It was raised from the seabed some 390 km off the Amami Islands on Sept. 11.
During his Sept. 17 summit with Prime Minister Junichiro Koizumi in Pyongyang, North Korean leader Kim Jong Il admitted his country's military has operated spy ships in waters near the Japanese archipelago.