Yanbian "Earthquake" 4.5-Magnitude Artificial Seismic Activity Caused by North Korea's Nuclear Test, Yanbian "Thought It Was An Earthquake", Students Were Urgently Evacuated To The Playground. "Earthquake! Run fast!" At around 9 a.m. yesterday, residents of the eight counties and cities of Yanbian Prefecture, Jilin Province, all felt the tremors caused by the earthquake. Many teachers and students who were having class at school also felt the tremors, and they timely evacuated the students to a safe area. Reporters learned from the Yanbian Prefecture Seismological Bureau that, this earthquake was caused by , with a magnitude of .