North Korea sub-launched missile traveled 20 miles, South's military says

SEOUL, April 25 (UPI) -- North Korea's submarine-launched ballistic missile firing was successful, South Korea military said.

The missile that was fired through a vertical launch system involved a cold launch, where the missile is ejected by gas, South Korean news service News 1 reported.

The North's missile development is moving at a rate faster than previously estimated, but the South's responses aren't moving quickly enough, the military source said.

"The SLBM did not attain the range of projected 190 miles but did reach up to 20 miles after launch," the source said.

Some technical progress still needs to be made, Seoul's Defense Ministry said Monday.

But other defense analysts like Moon Geun-sik said North Korea has virtually completed a series of underwater tests that are part of its SLBM program.

On land, Pyongyang has deployed about 300 multiple-rocket launchers near the heavily fortified demilitarized zone, Yonhap reported.

The 122-mm rocket launchers can fire weapons with a 25-mile range, South Korean military sources said.

"The North has been deploying the new rocket launchers with regimental units along the DMZ since 2014," said a source.

Pyongyang could send as many as 9,000 rockets into South Korea if it simultaneously fired all launchers at the border, according to Yonhap.

Seoul is also raising concerns about the rising possibility of a fifth nuclear test.

Japan, South Korea and the United States are ready to implement additional sanctions in the case of a fifth test, a senior Foreign Ministry official told press.

The unilateral sanctions could cover any remaining loopholes in the U.N. sanctions resolution that passed in March, according to the official.