Fox News has a report that says an unnamed US official has confirmed that North Korea did, in fact, detonate a nuclear bomb. They are also saying the seismic data indicates that the bomb yield may have been smaller than it was thought it would be. That one may be a reach, however since we simply do not know what they were testing. No do we know what configuration the device was. In other words, we have no idea if it was in a deliverable package. There is an enormous amount of conflicting information right now.
The official said, however, that initial readings from South Korea reported only a 3.58-magnitude seismic reaction, which is smaller than what would be expected from the 4-kiloton explosion the communist nation sought. To put the bomb's capabilities in context, a 20-kiloton explosion could conceivably kill 200,000 people.
"North Korea may not have got what they wanted," the official said.
• Raw Data: North Korean Statement on Alleged Nuke Test
The U.S. Geological Survey, however, said it detected a 4.2-magnitude tremor at 10:35 p.m. EDT, which could mean the device was potentially deadlier than initially believed. Australia also said there was seismic confirmation that North Korea conducted a nuclear test.
"It was a success from their perspective in that they achieved a nuclear yield, though that is not very difficult," the official said. "It's within their technical capabilities."
This will take a while to sort out. The US is going to push for hard sanctions.