SEOUL, South Korea (AP) — Before meaning can be assigned to South Korean spy claims that North Korean leader Kim Jong Un likely sacked the country’s second most powerful official — his uncle — comes a fundamental question: Is it even true?

Seoul’s intelligence agency has a spotty track record of predicting what’s going on inside what may be the most secretive, unfriendly and difficult-to-navigate country in the world for outsiders.

Jang Song Thaek. Pic: AP.

South Korea’s National Intelligence Service is thought to get its information in part by closely monitoring Pyongyang’s media for signs of change; by talking to defectors in Seoul, with a priority given to high-ranking ones and those who claim continuing ties with North Koreans; and by cultivating contacts in the North. All these groups, of course, have their own agendas.

The already tough job is made worse by the lingering bitter rivalry between the two Koreas. Not only is the Korean Peninsula still in a technical state of war — a legacy of the 1950-53 Korean War, which ended without a formal peace treaty — but citizens of both countries cannot legally visit or contact the other without government permission.

North Korean media have so far been silent, but it might be only a matter of time before outsiders learn if the NIS is right about Jang Song Thaek, a man widely seen as a kingmaker who guided his young nephew as he consolidated power. Pyongyang’s political and military elite may gather Dec. 17 to mark the second anniversary of the death of Kim’s father, Kim Jong Il.

Kim Jong Un has reportedly overseen other purges of senior officials, though none as high profile as this one, if confirmed.

For now, however, some analysts question the accuracy of the spy agency’s claim Tuesday that Jang may have been dismissed, which appears to be based largely on Jang’s nearly monthlong disappearance from North Korean media, something not unheard of in the leader’s circle, and the agency’s belief that two of his associates were publicly executed.

Here’s a look at past hits and misses by South Korea’s spy service:

ISLAND ATTACK:

Many in Seoul saw an intelligence breakdown in the spy agency’s failure to predict North Korea’s artillery bombardment of a front-line South Korean island in November 2010 that killed two civilians and two marines. At a closed-door parliamentary committee meeting after the attack, lawmakers said then spy chief Won Sei-hoon told them that his agency had intercepted North Korean communication indicating such an attack two months before it occurred but dismissed it as routine rhetoric.

KIM JONG IL’S HEALTH

The intelligence agency rejects allegations that it misjudged the repercussions of Kim Jong Il’s deteriorating health in the years before his 2011 death by telling South Korean officials that the government faced imminent collapse. Instead, the agency says, it advised them that Kim remained in control of his government but that its instability had increased slightly because of his health problems and a botched currency revamp in 2009.

KIM JONG IL’S DEATH:

The NIS was widely criticized because of reports it learned of Kim Jong Il’s 2011 death more than two days after it occurred, and in the same way that everyone else first heard of it: when a tear-choked North Korean television announcer read a formal statement. South Korean spies responded that they weren’t alone — no intelligence agency in the world knew about the death before the North’s public announcement, they say.