SEOUL, South Korea (AFP) – An undersea earthquake off the coast of North Korea was not caused by a nuclear test, the South’s media reported Thursday. The 5.9-magnitude quake struck about 190 kilometers (120 miles) south-east of the reclusive state’s third largest city, Chongjin, in the early hours of Thursday, according to the United States Geological Survey. North Korea has staged five nuclear tests — including two last year — and has made a significant […]