North Korea claimed it safely tested its third nuclear device underground Tuesday, a move South Korea called an "unacceptable threat” and which has been condemned even by the North’s closest ally, China.
Hours after seismic activity was detected at the North's Punggye-ri nuclear test complex, North Korea's Central News Agency said the detonation used a smaller nuclear device compared to its two earlier nuclear tests and was conducted in a safe manner, Yonhap reported.
"The test was conducted in a safe and perfect way on a high level with the use of a smaller and light A-bomb unlike the previous ones, yet with great explosive power," KCNA said in the English translation. "The specific features of the function and explosive power of the A-bomb and all other measurements fully tallied with the values of the design, physically demonstrating the good performance of the [North Korean] nuclear deterrence that has become diversified."
Once confirming the nuclear test occurred, South Korea said in a statement the test violated U.N. Security Council resolutions.
The nuclear test "is an unacceptable threat to peace and security on the Korean Peninsula and in the region and a head-on challenge to the international community," the statement said. "North Korea won't be able to avoid grave responsibility."
President Obama called the test a "highly provocative act" that violates the country's obligations under "numerous" U.N. Security Council resolutions, is contrary to its commitment to the so-called Six Party Talks and increases the risk of proliferation.
"North Korea's nuclear weapons and ballistic missile programs constitute a threat to U.S. national security and to international peace and security," Obama said in a statement. "The United States remains vigilant in the face of North Korean provocations and steadfast in our defense commitments to allies in the region."
The test blast was also condemned by in the U.S by the chairman of the House Armed Services Committee, who said it was “unfortunate that on the same day the President of the United States plans to announce further reductions in U.S. nuclear weapons, we see another hostile regime unimpressed by his example.”Rep. Howard P. "Buck" McKeon, R-Calif., also used the opportunity to argue against any cuts in the nuclear arsenal, however, because of the possibility of $500 billion in Defense cuts that could be forced by sequester.
China also weighed in against its erratic ally.
"The Democratic People's Republic of Korea, heedless of widespread international opposition, has again carried out a nuclear test, to which the Chinese government expresses its firm opposition," China’s Foreign Ministry said in a statement.
Japan, the only country ever attacked with nuclear weapons, called North Korea’s latest test “totally unacceptable.”“It constitutes a grave threat to Japan's security, represents a grave challenge to the international disarmament and non-proliferation regime centered on the Nuclear Non-proliferation Treaty, and seriously undermines the peace and security of Northeast Asia,” Japanese Prime Minister Shinzo Abe said in a statement.
The U.S. Geological Survey said seismic activity measured 4.9 on the Richter scale and was about 0.6 mile deep, suggesting a light earthquake; however, it was detected in an area where earthquakes are almost unknown, CNN said.
"It's a nuclear test," Jeffrey Lewis, director of the East Asia Non-proliferation Program at the Monterey Institute of International Studies in California, said. "That magnitude and that location -- it's awfully unlikely it's anything else."
The commission for the Comprehensive Nuclear Test Ban Treaty in Vienna said the seismic activity had "clear explosion-like characteristics," The New York Times reported. Experts told the newspaper the explosion appeared to be less powerful than the bomb the United States dropped on Hiroshima during World War II but significantly more powerful than the devices in North Korea's previous tests.
KCNA said the test was in response to the condemnation it received after launching a Unha-3 rocket Dec. 12 that North Korean officials said was tantamount to encroaching on the country's sovereignty. It said the test boost the country's defense against security threats from abroad and help ensure peace and stability on the Korean Peninsula and in the surrounding region.
Military.com contributed to this report.