Satellite imagery of North Korea’s Pongwha Chemical Complex gathered over the last four years indicates the possible expansion of some of the refinery’s facilities.

Specifically, at some point between 2015 and 2017, the Pongwha refinery may have added a catalytic cracking unit, which could allow the facility to produce lighter oils like gasoline and diesel more efficiently.

“(The imagery) indicates that the added equipment appears to be a catalytic cracker, though there are many questions about how it might be operated,” Dr. David Fridley, formerly with Caltex, told NK Pro.

The addition came