The former director of the Los Alamos National Laboratory in the U.S. says that during a trip to North Korea earlier this month, the North showed him a uranium enrichment facility at the Yongbyon nuclear site with two-thousand centrifuges.

Siegfried Hecker, now a professor at Stanford University, disclosed the report following his visit to the North on November 12th.

Hecker said the North told him that the facility can produce eight-thousand kilograms of enriched uranium and as much as 40 kilograms of highly enriched uranium each year.

Hecker said North Korean officials told him that the North made the centrifuges at home, based on Dutch and Japanese models.

The professor said he was “stunned” by the sophistication of the facility.

Hecker also cited a technical manager he met at the Yongbyon facility as saying that Pyongyang will work for progress in the six-party nuclear talks and on the 2005 six-way joint statement.