Beijing is not taking any chances: U.S. officials said on Thursday there was a higher-than-usual level of activity by Chinese bombers, signaling a possible heightened state of readiness by China, although the officials played down concern and left open a range of possible reasons. At the same time a Kremlin spokesman declined to comment on media reports that Russia was moving military hardware and troops toward the border with North Korea, the RIA news agency quoted him as saying.
U.S. and South Korean officials have been saying for weeks that the North could soon stage another nuclear test in violation of United Nations sanctions, something both the United States and China have warned against. That test could likely take place on April 25, when North Korea marks the 85th anniversary of the foundation of its Korean People's Army, an important anniversary that comes at the end of major winter military drills, South Korea's Unification Ministry spokesman Lee Duk-haeng said.
As Reuters reports, top envoys from the United States, South Korea and Japan on North Korea are due to meet on Tuesday, South Korea's foreign ministry said, to "discuss plans to rein in North Korea's additional high-strength provocations, to maximize pressure on the North, and to ensure China's constructive role in resolving the North Korea nuclear issue".
http://www.zerohedge.com/news/2017-04-21/south-korea-heightened-alert-north-prepares-major-army-event