North Korea says it tested a hydrogen bomb on Wednesday.
朝鲜声称周三试爆了氢弹。

The U.S. Geological Survey reported a 5.1 magnitude earthquake early Wednesday (UTC) near the site of previous North Korean nuclear tests.
美国地质调查局报告称，周三早些时候在靠近朝鲜之前的核试验基地附近发生了一场5.1级的地震。

The test site is in the mountainous northeastern part of the country, near the border with China.
该试验基地位于该国东北部山区，靠近中国边境。

North Korea announced the test on its state-run broadcast. The announcer said the test was "a self-defensive measure to thoroughly protect our nation's autonomy."
朝鲜在其国家电视台上宣布了这次试爆。播音员表示，这是试爆是“彻底维护我国主权的一种自卫措施。”

A spokesman from the National Security Council in the United States says it is too soon to confirm North Korea's claim.
美国国家安全委员会一位发言人表示，现在要确认朝鲜的说法尚为时过早。

But if the claim is true, he says the U.S. "will respond appropriately to any and all North Korean provocations."
但是如果这一说法属实，他说美国将对朝鲜的任何挑衅行为做出适当回应。

The last confirmed nuclear test by North Korea came in 2013.
朝鲜上次被证实的核试验发生在2013年。

If it was a nuclear test, an analyst from Korea Defense Network says, it was more powerful than previous tests based on the seismic activity it produced.
韩国国防部一位分析师表示，根据它造成的地震活动来看，如果这次真是核试验，它比之前的核试验的强度要更大。

"North Korea's nuclear test could have been 2.5 times more powerful than Hiroshima," he said.
他说，“朝鲜核试验的强度可能是广岛那次核爆的2.5倍以上。”

But intelligence officials from South Korea say they think the blast was not that powerful. They think the test produced an explosion less than half as strong as the one in Hiroshima during World War II.
但是韩国情报官员表示，他们认为这次爆炸没有那么强大。他们认为，这次核试验产生爆炸的强度不足二战期间广岛那次的一半。

Both South Korean President Park Geun-Hye and Japanese Prime Minister Shinzo Abe condemned the test.
但是韩国总统朴槿惠和日本首相安倍晋三都强烈谴责了这次核试验。

Abe says, "North Korea's nuclear test is a serious threat to our nation's security and absolutely cannot be tolerated."
安倍晋三说，“朝鲜的核试验严重威胁到我国的国家安全，这是绝对不能容忍的。”

The United Nations Security Council will hold an emergency meeting Wednesday to discuss North Korea's claim of a test.
联合国安理会周三将召开紧急会议讨论朝鲜宣称的核试验。

Last year, North Korean leader Kim Jong Un said his country had developed a hydrogen bomb. If North Korea's claim turns out to be true, it will have been the second nuclear test under Kim's leadership.
去年，朝鲜最高领导人金正恩表示，该国已经研制出了氢弹。如果朝鲜的说法被证实，这将是金正恩领导下的第二次核试验。