North Korea Says Nuclear Test Successful

A South Korean Army soldier walks by a signboard showing distances to North Korea's capital Pyongyang from Imjingang railway station, in the Imjingak Pavilion, near the demilitarized zone (DMZ) of Panmunjom, South Korea , Sunday, Oct. 8, 2006. North Korea's threatened nuclear test moved to the top of the diplomatic agenda Sunday as Japanese Prime Minister Shinzo Abe flew to China to try to coordinate international pressure on Pyongyang to desist. (AP Photo/Ahn Young-joon) (Ahn Young-joon - AP)

Japan's top government spokesman said if confirmed, the North Korean test would post a serious threat to the stability in the region and a provocation.

South Korea's presidential spokesman says Seoul will "sternly respond" to North Korea nuclear test and the Defense Ministry raised the military alert level.

The North's official Korean Central News Agency said the underground test was performed successfully and there was no dangerous radioactive leakage as a result of the underground test.

North Korean scientists "successfully conducted an underground nuclear test under secure conditions," the KCNA report said, adding this was "a stirring time when all the people of the country are making a great leap forward in the building of a great prosperous powerful socialist nation."

"It marks a historic event as it greatly encouraged and pleased the ... people that have wished to have powerful self-reliant defense capability," the KCNA statement went on to say. "It will contribute to defending the peace and stability on the Korean Peninsula and in the area around it."

South Korean intelligence officials said the seismic wave had been detected in North Hamkyung province, according to South Korea's Yonhap news agency. It said the test was conducted at 10:36 a.m. (9:36 p.m. EDT Sunday) in Hwaderi near Kilju city on the northeast coast, citing defense officials.

An official at South Korea's seismic monitoring center confirmed a magnitude-3.6 tremor felt at the time North Korea said it conducted the test was not a natural occurrence. The official spoke to The Associated Press on condition his name not be used, because he was not authorized to talk about the sensitive information to the media.

Australia also said there was seismic confirmation that North Korea conducted a nuclear test.

Japanese Prime Minister Shinzo Abe was skeptical as he arrived for a summit in South Korea.

"We must collect and analyze information to determine whether a test was actually held," he said.

South Korean President Roh Moo-hyun convened a meeting of security advisers over the issue, Yonhap reported, and intelligence over the test has been exchanged between concerned countries.

Kyodo News agency reported that the Japanese government has set up a taskforce in response to reports of the test.