Artificial tremors in North Korea
First successful hydrogen bomb test announced
North Korean test of a hydrogen bomb, Jan 6, 2016 : People watch a TV report on North Korea's test of a hydrogen bomb at Seoul railway station in Seoul, South Korea. North Korea announced on Wednesday it has conducted a test of a hydrogen bomb successfully. South Korea's defence ministry said the North's new nuclear test doesn't appear to be hydrogen-based, in consideration of the intensity of the tremor, local media reported. (Photo by Lee Jae-Won/AFLO) (SOUTH KOREA)