North Korea's Kim oversees test-fire of surface-to-air missiles

(Reuters) -North Korean leader Kim Jong Un oversaw the test-firing of the country's latest anti-aircraft missile system on Thursday, state media KCNA reported, as some experts said Pyongyang was probably getting technical help from Russia to perfect such systems.

Kim thanked what was referred to as a research group for the system. The test-firing showed it was "highly reliable" and its combat response was "advantageous," KCNA said in its report on Friday.

The test conducted by North Korea's Missile Administration was to examine the performance of a system whose production has already begun, it said.

KCNA did not specify where the test was held, but said Kim was joined by members of the Central Military Commission of the ruling Workers' Party of Korea.

Photographs supplied by KCNA showed a plume from a missile soaring into the sky and a mid-air explosion. Other images showed Kim apparently observing the test and then smiling.

Experts said Pyongyang might be receiving help from Russia for the anti-aircraft missile system, particularly given how security ties have become increasingly entwined."In the past North Korea has introduced Soviet weapon systems and developed weapons based on them, and it is highly likely that Russia has given correspondingly what North Korea demands because of the strengthening of cooperation," said Shin Seung-ki, head of research on North Korea's military at the state-run Korea Institute for Defense Analyses. South Korea's national security adviser said last year that Russia had provided North Korea with anti-air missiles and air defence equipment in return for sending troops to support Moscow in its war against Ukraine.

Shin also noted although North Korea has made ballistic missiles on its own, it was far harder to produce interceptor missiles without additional help.

"It's much more complicated because there's not just missiles, but a detection and tracking radar, and there's a command and control system," Shin said.

South Korea's military was aware in advance of a possible missile launch which ended up taking place about 9 a.m. (0000 GMT) on Thursday in North Korea, Yonhap News Agency reported, citing an official from the Joint Chiefs of Staff (JCS).

Seoul and Washington wrapped up their latest annual joint military drills, known as Freedom Shield, on Thursday. They say such exercises are defensive, but Pyongyang has long demanded a halt to U.S.-South Korea joint exercises, branding them a prelude to an invasion.

In a statement carried by KCNA, a spokesperson for North Korea's defence ministry criticized the latest joint drills by South Korea and the United States, calling them "reckless" and "a rehearsal of war."

All options for containing the U.S. and South Korea were being considered, including the use of the "most destructive and deadly military means", the statement said, while urging the militaries of both countries to stop their acts.

(Reporting by Hyunsu Yim; Additional Reporting by Joyce Lee; Editing by Nia Williams, Ed Davies)