The following are excerpts of the Joint Civilian-Military Investigation Group (JIG) report on the sinking of a South Korean navy ship in March implicating North Korea.
Damage to ship
A shockwave and bubble effect caused significant upward bending of the CVK (Center Vertical Keel), compared to its original state, and shell plate was steeply bent, with some parts of the ship fragmented.
On the main deck, fracture occurred around the large openings used for maintenance of equipment in the gas turbine room and significant upward deformation is present on the port side. Also, the bulkhead of the gas turbine room was significantly damaged and deformed.
The bottoms of the stern and bow sections at the failure point were bent upward. This also proves that an underwater explosion took place.
We have found evidence of extreme pressure on the fin stabiliser, a mechanism to reduce significant rolling of the ship; water pressure and bubble effects on the bottom of the hull; and wires cut with no traces of heat. All these point to a strong shockwave and bubble effect causing the splitting and the sinking of the ship.
Impact on crew
The survivors made a statement that they heard a near-simultaneous explosion once or twice, and that water splashed on the face of a port-side lookout who fell from the impact.
A sentry on the shore of Baekryong-do stated that he witnessed an approximately 100-metre-high "pillar of white flash" for 2-3 seconds. The aforementioned phenomenon is consistent with damage resulting from a shockwave and bubble effect.
No trace of fragmentation or burn injury were found [on the deceased service members], but fractures and lacerations were observed. All of these are consistent with damage resulting from a shockwave and bubble effect...
Evidence of torpedo
As for conclusive evidence that can corroborate the use of a torpedo, we have collected propulsion parts, including propulsion motor with propellers and a steering section from the site of the sinking.
The evidence matched in size and shape with the specifications on the drawing presented in introductory materials provided to foreign countries by North Korea for export purposes...
The marking in Hangul, which reads "1번(or No. 1 in English)", found inside the end of the propulsion section, is consistent with the marking of a previously obtained North Korean torpedo. The above evidence allowed the JIG to confirm that the recovered parts were made in North Korea.
Also, the aforementioned result confirmed that other possible causes for sinking raised, including grounding, fatigue failure, mines, collision and internal explosion, played no part in the incident...
- ROKS "Cheonan" was split apart and sunk due to a shockwave and bubble effect produced by an underwater torpedo explosion.
- The explosion occurred approximately 3m left of the centre of the gas turbine room, at a depth of about 6-9m.
- The weapon system used is confirmed to be a high explosive torpedo with a net explosive weight of about 250kg, manufactured by North Korea...
We confirmed that a few small submarines and a mother ship supporting them left a North Korean naval base in the West Sea 2-3 days prior to the attack and returned to port 2-3 days after the attack...
The torpedo parts recovered at the site of the explosion by a dredging ship on 15 May, which include the 5x5 bladed contra-rotating propellers, propulsion motor and a steering section, perfectly match the schematics of the CHT-02D torpedo included in introductory brochures provided to foreign countries by North Korea for export purposes. The markings in Hangul, which reads "1번(or No. 1 in English)", found inside the end of the propulsion section, is consistent with the marking of a previously obtained North Korean torpedo. Russian and Chinese torpedoes are marked in their respective languages...
Based on all such relevant facts and classified analysis, we have reached the clear conclusion that ROKS "Cheonan" was sunk as the result of an external underwater explosion caused by a torpedo made in North Korea. The evidence points overwhelmingly to the conclusion that the torpedo was fired by a North Korean submarine. There is no other plausible explanation.