North Korea preparing to restart atomic facility

Tensions also rose elsewhere on the Korean peninsula, with the North warning the South against sending naval ships into its waters and threatening warfare as it reportedly shifted an arsenal of missiles to a nearby island for more test launches.

The warning came hours after a South Korean newspaper reported that a U.S. spy satellite detected signs the North had positioned about 10 missiles near the disputed sea border after test-firing two short-range missiles on Tuesday. The Chosun Ilbo report cited an unidentified South Korean official.

Yongbyon, located about 60 miles north of Pyongyang, has three main facilities: a 5-megawatt reactor, a plutonium reprocessing plant and a fuel fabrication complex.

The reactor is the centerpiece of the complex, with the facility stretching more than a mile along the Churyong River, satellite images show.

The reprocessing center to the south of the reactor is capable of extracting weapons-grade plutonium from spent fuel rods. Thousands of them remain in storage but would likely be moved to the reprocessing plant as a next step. South of the reprocessing center, fuel rods are made from natural uranium in the fuel fabrication complex that lies tucked into a bend in the Churyong River.

A second reactor with the potential to produce much higher quantities of plutonium has not been completed.

North Korea was to dismantle the Yongbyon nuclear complex in return for diplomatic concessions and energy aid equivalent to 1 million tons of oil under the deal with the U.S., South Korea, China, Russia and Japan.

But the accord hit a snag in mid-August when the U.S. refused to remove North Korea from the terrorism list until the North accepts the plan for allowing a full check of the list of nuclear assets the North says it has.

U.S. chief nuclear negotiator Christopher Hill recently returned to Washington from a trip to North Korea meant to jump-start the talks, but the State Department has declined to provide details of his meetings.

For the U.S., the North Korean nuclear reversal is the second major setback this decade — Yongbyon was under IAEA seal in December 2002 when Pyongyang ordered U.N. inspectors out of the country and restarted its atomic activities, unraveling a deal committing the U.S. to help the North build a peaceful nuclear program.

North Korea quit the Nuclear Nonproliferation Treaty in January 2003. Then on Oct. 9, 2006, it set off an underground test explosion of a nuclear weapon. There was widespread international condemnation, but the U.S. also softened its position and the six-nation deal soon followed.

Scientists began disabling the Yongbyon reactor a year ago, and in June the North blew up its cooling tower in a dramatic show of commitment to the pact.

Eight of the 11 steps needed to disable the reactor had been completed by July, North Korean officials said.

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