N Korea preparing for an underground N-test?

NEW YORK: North Korea may be preparing for an underground test of a nuclear bomb, a media report on Friday said quoting two unidentified American officials.

"It is the view of the intelligence community that a test is a real possibility," it said quoting a senior US State Department official.

The official told ABC News that a US intelligence agency has recently observed "suspicious vehicle movement" at a suspected North Korean test site.

The activity included the unloading of large reels of cable outside P'unggye-Yok, an underground facility in northeast North Korea.

Cables can be used in nuclear testing to connect an underground test site to outside observation equipment. The intelligence was brought to the attention of the White House last week, the network reported.

Even before this, most recent intelligence, ABC said there has been growing concern within the US government that North Korea has been moving towards a nuclear test.

North Korea is believed to have enough nuclear material to build as many as a dozen nuclear bombs, but it has never tested one. A successful test would remove any doubt that North Korea is a nuclear power.

On July 4, North Korea conducted seven ballistic missile tests, which provoked international condemnation, including a unanimous United Nations Security Council resolution condemning its actions.

A nuclear test, however, would be seen as a much greater provocation than the missile tests, ABC said, noting that so far only seven other nations in the world have ever conducted nuclear tests.

US officials, the report said, fear a nuclear test could provoke a nuclear arms race in East Asia, forcing Japan and South Korea to develop their own nuclear weapons.

"A nuclear test is going to be alarming and troubling for everyone and would cause a very strong reaction I think from all of North Korea's neighbors," former National Security Council official Michael Green, told the network.

US officials, ABC said, caution that the intelligence is not conclusive. Last year US spy satellites picked up suspicious activity at suspected test sites in North Korea, leading some to predict an imminent nuclear test, but nothing happened.

Underground nuclear tests are notoriously difficult to detect ahead of time. US intelligence agencies, for example, failed to predict nuclear tests by India in 1998.

Officials say it is possible that North Korea may either be putting on a show for American spy satellites to get attention, or may conduct a nuclear test in an entirely different location.

Some analysts believe Kim Jong Il may feel the only way to be taken seriously is to prove that North Korea is a nuclear power.

Asked what the United States would do in response to a nuclear test, a senior U.S. official told ABC News, "We would try to hermetically seal the hermit kingdom."

The official said the United States would immediately push for sanctions to cut North Korea's ties to the outside world. Another possible option would be a naval blockade of North Korea.