South Korea has accused the reclusive North of torpedoing one of its warships, heightening tension in the economically powerful region and testing the international position of China, Pyongyang's only major backer.

Advertising Read more

AFP - A North Korean submarine torpedoed one of South Korea's warships near the disputed maritime border in March, investigators said Thursday, prompting heated denials and threats of war from the North.

The South's President Lee Myung-Bak promised "resolute countermeasures" and the United States, Britain and Australia strongly condemned the attack which claimed 46 lives.

The communist North said the report, by a multinational investigation team, was based on "sheer fabrication". It threatened "all-out war" in response to any attempt to punish it.

"The evidence points overwhelmingly to the conclusion that the torpedo was fired by a North Korean submarine," the team said, releasing its report on the March 26 sinking at a nationally televised press conference.

"There is no other plausible explanation."

Seoul's closest ally the United States called the attack "one more instance of North Korea's unacceptable behaviour and defiance of international law.

"This attack constitutes a challenge to international peace and security and is a violation of the armistice agreement" which ended the 1950-53 war, said White House spokesman Robert Gibbs.

British Foreign Secretary William Hague said the North had shown "a total indifference to human life". British experts joined the probe, along with specialists from the United States, Australia and Sweden.

The sinking caused outrage in South Korea, which declared five days of national mourning. Cross-border relations, which have been frosty for months, went into a deep chill.

But Seoul has apparently ruled out a military counter-strike for fear of igniting all-out war. It is likely to ask the United Nations Security Council to slap new sanctions on the North.

This would need agreement from China, a veto-wielding council member and the North's ally, which has indicated it first wants to see strong evidence.

"Resolute countermeasures will be taken against North Korea," Lee told Australian Prime Minister Kevin Rudd in a phone conversation, according to Lee's office.

South Korea, through strong international cooperation, "should make North Korea admit its wrongdoing and return as a responsible member of the international community", added Lee, whose National Security Council will meet Friday to weigh its reaction.

Rudd called for an "appropriate" international response.

The sinking near the Yellow Sea frontier flashpoint was the worst apparent cross-border provocation since the downing of a South Korean airliner in 1987 with the loss of 115 lives.

The investigators laid out apparently damning evidence against Pyongyang, which is thought by some analysts to have acted in revenge for a naval firefight last November in the area.

The 1,200-tonne corvette was split apart by a shockwave and bubble effect produced by the underwater explosion of a 250 kilogramme (550 pound) homing North Korean torpedo, the report said.

It said parts salvaged from the Yellow Sea "perfectly match" a type of torpedo that the North has offered for export.

A marking in Korea's Hangeul script was found on one recovered section, and matches markings on a stray North Korean torpedo recovered by the South seven years ago, investigators said.

The report said the attack was likely carried out by a small submarine.

"We confirmed that a few small submarines and a mother ship supporting them left a North Korean naval base in the West (Yellow) Sea 2-3 days prior to the attack and returned to port 2-3 days after the attack."

The North's top decision-making body the National Defence Commission, in a statement on the official news agency, said it would send its own investigators to the South to check the purported evidence.

Seoul rebuffed the proposal, saying a commission overseeing the armistice would carry out its own probe.

"Our army and people will promptly react to any 'punishment' and 'retaliation' and to any 'sanctions' infringing upon our state interests with various forms of tough measures including an all-out war," the North's statement said.

It threatened in future to respond to any small border incident with a "merciless strong physical blow".

The North refuses to accept the Yellow Sea borderline where the Cheonan went down. The area was the scene of deadly clashes in 1999 and 2002 and the firefight last November left a North Korean boat in flames.



Daily newsletterReceive essential international news every morning Subscribe