Satellite photos demonstrate N. Korea nuclear activity

New satellite photos show that North Korea has resumed some work on a nuclear reactor that could enable the communist state to increase stocks of weapons-grade plutonium.

Washington-based Institute for Science and International Security (ISIS), which has often produced authoritative research on North Korea and Iran, ordered the images from a commercial satellite firm. U.S. intelligence is believed to have higher-resolution images but they are classified.

The new data comes to light as six-country talks designed to end the North's nuclear weapons program have stalemated in Beijing. Negotiators will try again to break the deadlock on Thursday.

Construction of the larger, 50-megawatt reactor was halted at Yongbyon when the North and the United States signed a nuclear agreement in 1994.

The accord fell apart in 2003 and beginning at the end of June 2005, there were reports in the Japanese press that construction at the site had resumed.

According to the latest data the North Koreans may prepare to start full-scale construction or it could mean they are aware U.S. satellites are watching the site and want to provide confusing information.

The five-megawatt reactor began operating in 1987 but was shut down in 1994 under the U.S.-North Korea agreed framework, when 8,000 spent fuel rods were removed. It was restarted again in February 2003 after the deal fell apart.

It was shut down again in April 2005, presumably so spent fuel could be removed and new fuel installed. The new photos, which show a steam plume from the facility, "support North Korean statements that the five-megawatt reactor is now operating again,".

U.S. intelligence estimates Pyongyang has already produced enough bomb-grade plutonium fuel from the five megawatt reactor for nine or more weapons.

Experts say the five-megawatt reactor can generate enough plutonium for one bomb per year. The 50-megawatt reactor could produce vastly more, Reuters reports.