By Lee Tae-hoon
Experts probing the cause of the sinking of a warship that took the lives of 46 South Korean sailors in late March have concluded that a torpedo was responsible for the naval tragedy, a government source said Friday.
It said a team of civilian and military specialists confirmed that a chemical substance used in making torpedoes has been identified from residue found on the funnel, the stern, as well as the seabed, where the broken half of the ship rested.
"Each of the chemical elements of the explosives traces was confirmed as those of the RDX, a more powerful explosive than TNT," he said
"They came to the conclusion because the RDX is used for torpedoes, not sea mines."
RDX stands for research department explosive. It is a highly explosive compound, commonly used as a main ingredient in plastic explosives.
About four alloy fragments have also been found in the salvaged wreckage and an analysis has suggested that they were made of an aluminum-magnesium alloy used to produce a torpedo's casing, the official said.
The government is expected to make public its findings around May 20 as an investigation is underway to determine the manufacturer of the torpedo and who fired it.
The multinational investigation team is also closely looking into the possibility that a North Korean submarine fired a German-made torpedo used both by South Korean and American navies in an attempt to dodge its responsibility.
Experts from the United States, Sweden, Australia and Britain have been jointly carrying out the probe along with South Korean specialists in an effort to improve its transparency and impartiality.
Once the investigation is complete, the government may invite specialists from China and Russia, two allies of North Korea, to provide them with a first-hand look at the ship's wreckage, another government official said.
President Lee Myung-bak told Chinese President Hu Jintao last Friday in a summit in Shanghai that Seoul would carry out a scientific and objective investigation into the tragedy and promptly inform Beijing of the results.
The Chosun Ilbo, a local daily, reported that circumstantial evidence suggests that the North's Reconnaissance Bureau, the agency in charge of espionage operations against the South, masterminded the sinking of the 1,200 ton warship in the West Sea, the scene of bloody naval clashes in 1999, 2002 and 2009.
Citing an unnamed government source, the paper claimed that South Korean and U.S. intelligence agencies have collected three decisive pieces of evidence that support the growing suspicion of Pyongyang's involvement.
The bureau reportedly responsible for the incident was created through a merger of various North Korean spy agencies in February last year and is led by the hawkish Lt. Gen. Kim Yong-chol, the paper said.
Meanwhile, senior South Korean and U.S. officials held talks to draw up necessary security measures following the Cheonan incident, Friday, a day after the Security Policy Initiative (SPI), a regular dialogue aimed at addressing bilateral security issues between Seoul and Washington.
The meeting took place between Kim Hong-kyun, director of the foreign ministry's Korean Peninsula peace regime bureau, and Joseph Donovan, principal deputy assistant secretary of state for East Asian, and Pacific affairs, who was in Seoul to attend the SPI.
Sources say the two sides worked out "necessary security measures" over the naval incident.
The military is considering taking more aggressive action against North Korean ships crossing the Northern Limit Line (NLL), the de facto maritime border Pyongyang has refused to recognize.
North Korean vessels violated the sea border 23 times last year, according to the military.
The Navy is considering spending less time on radio warnings before moving on to firing warning shots and then aimed shots, according to a military source.
A South Korean patrol ship issued a radio warning for about an hour when a North Korean military vessel crossed the NLL in November last year, which led to a naval skirmish in waters southwest of Daecheong Island.
"Up until now, we have taken some time in giving radio warnings when North Korean ships have violated the sea border," the official said.
"After the Cheonan incident, we're considering operating the rules of engagement in a speedier way."
천안함서 어뢰 화약성분 검출
천안함 침몰의 원인을 조사 중인 전문가들은 해상 재난의 원인은 어뢰라고 결론 지었다고 정부 소식통은 7일 전했다.
시민 및 군 전문가 팀은 어뢰를 만드는데 사용된 화학 물질이 함미와 함미가 발견된 해저에서 모두 확인됐다고 말했다.
다국적 조사팀은 북한 잠수함이 남한과 미국이 모두 사용하는 독일제 어뢰를 사용해 책임을 회피하려 한 가능성에 대해 정밀히 검토하고 있다.
정부는 현재 조사단이 어뢰의 제조업체와 누가 발사했는지에 대해 조사 중에 있어 이달 20일쯤 조사 결과를 공개할 예정이다.