By Lee Chi-dong
WASHINGTON, Aug. 7 (Yonhap) -- North Korea appears to have doubled the floor size of its uranium enrichment facility in Yongbyon, apparently in line with its stated plans to advance related technology and production, a U.S. research center said Wednesday, citing recent satellite imagery.
The Washington-based Institute for Science and International Security (ISIS) said the North seems to have expanded a building in the fuel fabrication complex that houses a gas centrifuge plant for uranium enrichment.
"The area is now covered by an extended roof that is roughly twice the size of the previous one," it said in a report. "A doubling of available floor space at this building could allow a doubling of the number of centrifuges installed there."
The institute made public three photos of the site taken by commercial satellites on May 3, 2012, June 10, 2013, and July 28, 2013, respectively. The photos show progress in construction work.
North Korea has claimed that it is running the facility to generate energy.
But the international community suspects that the reclusive communist nation may be trying to produce weapons-grade uranium in addition to its decades-old plutonium-based nuclear program.
David Albright and Robert Avagyan, co-authors of the report, pointed out it is possible that some low-enriched uranium produced there could have been further enriched at a secret centrifuge site to produce weapons-grade uranium.
"Or weapon-grade uranium could have been made at the Yongbyon plant. A significant question remains whether North Korea has made weapon-grade uranium, and if so, how much it has made," they said.
In April, North Korea announced that its nuclear scientists will begin work "readjusting and restarting" a uranium enrichment plant and a graphite-moderated, 5-megawatt reactor in the Yongbyon complex.