A United States website specializing in North Korea analysis says that the uranium enrichment plant at the Yongbyon Nuclear Scientific Research Center appears to have continued operations.

Nuclear expert Peter Makowsky and two satellite imagery experts presented the assessment in an article posted on 38 North, citing commercial satellite imagery of the North Korean nuclear facility taken from January and February.

According to the experts, the imagery indicated that while the reactors remain inactive, the uranium enrichment plant has continued operations.

They said that in contrast to the reactor area of the complex, the plant exhibited continual signs of operation throughout the winter months.

The article said that while the imagery signatures for operation are subtle, there are a few that reoccur on a periodic basis, such as the arrival and departure of uniquely-configured, specialized railcars.