North Korea has moved what appears to be a mid-range missile to its east coast, according to South Korea's Yonhap news agency and Japan's Asahi Shimbun newspaper.  It’s not clear if the Musudan missile was equipped with a warhead, or if it’s there for a reason or just a show of force.

The Musudan is based on an old Soviet design.  It might have a range of up to 4,000 kilometers, but western observers haven’t seen any evidence that it’s even been tested. 

But if it can fly, it’s position puts all of South Korea and Japan within range, and possibly the US Military Base on Guam as well.

Rather than the People’s Army mobile missile launcher it was designed to be used with, the Musudan was moved to the coast via train.  There is a missile launch site on North Korea’s northeastern coast, which it has used to unsuccessfully test-fire long-range rockets in the past.