South Korea's military said the missiles were unlikely to have been intercontinental ballistic missiles (ICBM), which can reach the United States. The missiles flew on average 1,000 km (620 miles) and reached a height of 260 km (160 miles).
Some of the missiles landed in waters as close as 300 km (190 miles) from Japan's northwest coast, Japan's Defence Minister Tomomi Inada said in Tokyo.
Link: http://www.reuters.com/article/us-northkorea-missiles-idUSKBN16C0YU
Looks like North Korea is provoking again.
As to what is the reason behind that firing of ballistic missiles into the sea locate at Japan's northwest by the North Korean government still remains a mystery. But one thing is clear South Korea, Japan and America will not rest easy until they placed some security measures and and can be competent that if there will be missile attacks coming from North Korea.