An image taken last week by DigitalGlobe, a U.S.-based commercial satellite firm, shows new construction or excavation activity in an area surrounding a destroyed cooling tower at the Yongbyon site. Experts said the construction appeared to be the first sign of genuine activity at Yongbyon since 2008, when the cooling tower was demolished as part of an agreement made during now-stalled negotiations over the North’s nuclear program…

Albright said the activity could mean that North Korea is moving toward reopening Yongbyon as part of a plan to increase its stock of plutonium – now estimated at just less than 80 pounds. Then again, it could also be a move, said Joel S. Wit, a North Korea watcher and former State Department official, “for show, to pull our chains.” North Korea is well aware that its nuclear facilities are under almost constant surveillance by both intelligence and commercial satellites.