North Korea launched a ballistic missile - possibly from a submarine - into the Sea of Japan, South Korea’s military has said, in the latest in a series of tests by Pyongyang over recent weeks, writes The Guardian.

One ballistic missile was launched about 10:17am local time from the vicinity of Sinpo, South Korea’s joint chiefs of staff said, where North Korea keeps submarines as well as equipment for test firing submarine-launched ballistic missiles (SLBMs).

“Our military is closely monitoring the situation and maintaining readiness posture in close cooperation with the United States, to prepare for possible additional launches”, - the joint chiefs of staff said in a statement.

A South Korean newspaper, Joongang Ilbo, cited an unnamed military source as saying the government was “assuming that it was an SLBM test”.

The North is known to be developing a submarine-launched ballistic missile (SLBM) and previously carried out an underwater launch, although analysts said that one was likely to have been from a submerged platform rather than a submarine.