General vicinity of North Korean nuclear test preparation

There is new evidence that North Korea may be preparing for an underground test of a nuclear bomb, U.S. officials told ABC News.

"It is the view of the intelligence community that a test is a real possibility," said a senior State Department official.

A senior military official told ABC News that a U.S. intelligence agency has recently observed "suspicious vehicle movement" at a suspected North Korean test site.

The activity includes the unloading of large reels of cable outside P'unggye-yok, an underground facility in northeast North Korea. Cables can be used in nuclear testing to connect an underground test site to outside observation equipment.