In the wake of DPRK carrying out "crucial test", US Special Representative for North Korea Stephen Biegun arrived in Seoul on Sunday.Yonhap reported that Biegun arrived in Seoul on Sunday amid rising tensions over North Korea's "apparent rocket engine tests this month ahead of its year-end deadline for Washington to show flexibility in advancing their stalemated nuclear talks."His visit comes after North Korea on December 14 said it has conducted "another crucial test" at the Sohae Satellite Launching Ground."The research successes being registered by us in defence science one after another recently will be applied to further bolstering up the reliable strategic nuclear war deterrent of the Democratic People's Republic of Korea," a statement carried by North Korean stated media read.This came merely a week after it conducted a "very important" test at its key satellite launching station.The trip by US Special Representative has raised speculations that he could "visit the inter-Korean
