N Korea fires 'several' cruise missiles: Seoul military

North Korea fired another round of cruise missiles on Tuesday, according to Seoul's military, extending a week-long flurry of tests that Pyongyang has said include a new generation of weapons.

South Korea's military "detected several unknown cruise missiles launched into the West Sea of North Korea around 07:00 (2200 GMT)", Seoul's Joint Chiefs of Staff said in a statement.

South Korean and U.S. intelligence agencies "are conducting a detailed analysis", the JCS said.

"Our military is cooperating closely with the U.S. while strengthening surveillance and vigilance, and is closely monitoring North Korea's activities," it added.

Unlike their ballistic counterparts, the testing of cruise missiles is not banned under current U.N. sanctions on Pyongyang.

Cruise missiles tend to be jet-propelled and fly at a lower altitude than more sophisticated ballistic missiles, making them harder to detect and intercept.

Recent months have seen a sharp deterioration in ties between the two Koreas, with both sides jettisoning key tension-reducing agreements, ramping up frontier security, and conducting live-fire drills along the border.

Pyongyang has accelerated weapons testing in the new year, including tests of what it called an "underwater nuclear weapon system" and a solid-fuelled hypersonic ballistic missile.

On Monday, state media said North Korean leader Kim Jong Un had overseen the test launch of a new strategic cruise missile from a submarine.

Last week, Pyongyang said it had also conducted its first test of a new generation of strategic cruise missiles.

"It is believed that North Korea has commenced mass production of cruise missiles ordered by Russia," Ahn Chan-il, a defector-turned-researcher who runs...