With North Korea promising to conduct a third nuclear test soon, international intelligence communities have been looking for a telltale sign: Sealing the mouth of the newest of three underground tunnels at the country's Punggye-ri would indicate the country is ready to go. But it looks like the always-secretive rogue regime is maintaining that secrecy, with the South Korean military today reporting that North Korea has covered the tunnel's mouth so spy satellites can't observe what's going on, reports the New York Times.
It's not the first time Pyongyang has employed the tactic. Days before December's ballistic missile launch, it covered the launchpad. On Dec. 11, North Korea said technical problems had led to at least a week-long delay; but just a day later it launched the rocket, catching some intelligence officials off-guard. Still, the US and South Korea stand at the ready, armed with temblor monitoring stations and planes equipped with radiation detectors. (Read more North Korea stories.)