On March 7, South Korea revealed that its intelligence agencies spotted movement of cargo vehicles near the Sanumdong ICBM plant in Pyongyang. South Korea’s National Intelligence Service briefed the country’s lawmakers on this activity, saying the movement is “missile-related.” Both South Korea and the United States have declined to confirm the reports of missile activity. The Sanumdong facility was used to produce North Korea’s first ICBMs capable of reaching the U.S. mainland, including the longest-range Hwasong-15. These intelligence reports follow satellite imagery analysis released on March 4 by U.S. think tanks and South Korean media that indicates North Korea is rebuilding its Sohae Satellite Launching Station at Tongchang-ri.