North korea conducting a nuclear test. The news coming on north korean television. It appears to be far larger than the north's previous two nuclear tests. The u.N. Security council has now called an... See More
North korea conducting a nuclear test. The news coming on north korean television. It appears to be far larger than the north's previous two nuclear tests. The u.N. Security council has now called an emergency meeting. And the white house has issued a strongly-worded statement. Let's get, right now, to abc's martha raddatz in washington with the latest. Good morning to you, martha. Reporter: Good morning, josh. This test was big. As much as three-times the size of previous tests. It was bold. Even china, north korea's staunchest ally, had north korea not to test a nuclear weapon. This is the first nuclear test under kim jong-un, who said the test is aimed at ferocious u.S. Hostility towards north korea. In december, also successfully tested a long-range missile, capable of reaching hawaii. The white house is calling this a highly provocative act. And calling on actions from the international community. There's very little the u.S. Or the u.N. Can do at this point since strong sanctions are already in place. In fact, this morning, north korea is saying, we will by the international community as an act of war. And, josh, they say it will bring on relentless retaliatory attacks. We will certainly keep our eye on this. Martha, thank you for that.
This transcript has been automatically generated and may not be 100% accurate.