The International Atomic Energy Agency(IAEA) has assessed that the infrastructure of Kangson Complex, a suspected uranium enrichment plant in North Korea, shares characteristics with the reported centrifuge enrichment facility at the North’s Yongbyon nuclear complex. 

IAEA Director-General Rafael Grossi revealed the assessment in his opening remarks for the agency’s board of governors meeting in Vienna, Austria on Monday.

The IAEA chief said that in late February, work commenced on the construction of an annex to the main building in the Kangson Complex, significantly expanding the available floor space, adding the annex is now externally complete.

Grossi also said that the IAEA has observed intermittent cooling water discharge consistent with the operation of the Light Water Reactor at Yongbyon, adding there have been ongoing indications of the operation of the five megawatt reactor and the reported centrifuge enrichment facility.

The Kangson Complex on the outskirts of Pyongyang has long been identified and monitored by U.S. intelligence authorities as a secret nuclear facility. The complex is suspected to be another of the North’s uranium enrichment facilities in addition to the Yongbyon facility.