Kim Jong Un oversees missile firing drills

A day after South Korea's military detected the North launching several unidentified short-range projectiles into the sea off its eastern coast, North Korean state media showed leader Kim Jong Un observing live-fire drills of long-range multiple rocket launchers and unspecified tactical guided weapons.

Pyongyang: North Korean state media on Sunday showed leader Kim Jong Un observing live-fire drills of long-range multiple rocket launchers and unspecified tactical guided weapons, a day after South Korea's military detected the North launching several unidentified short-range projectiles into the sea off its eastern coast.

Pyongyang's official Korean Central News Agency said Kim expressed "great satisfaction" over Saturday's drills and stressed that his front-line troops should keep a "high alert posture" and enhance combat ability to "defend the political sovereignty and economic self-sustenance of the country."

The missile launches were a likely sign of Pyongyang's growing frustration at stalled diplomatic talks with Washington, which were meant to provide coveted sanctions relief in return for nuclear disarmament.

They also highlighted the fragility of the detente between the Koreas, which in a military agreement reached last September vowed to completely cease "all hostile acts" against each other on land, air and sea.

South Korea said it was "very concerned" about North Korea's weapons launches, calling them a violation of the agreements to reduce animosity between the countries.

The statement, issued after an emergency meeting Saturday of top officials at the presidential Blue House in Seoul, also urged North Korea to stop committing acts that would raise military tensions and join efforts to resume nuclear diplomacy.