AP/David Guttenfelder

Kim Jong-un, the 29-year-old leader of North Korea, hit headlines around the world today after his ex-girlfriend was reportedly executed in public.

It's a pretty remarkable story — the ex-girlfriend, popular singer Hyon Song-wol, was one of several who were reportedly executed by firing squad after being accused of making and s elling sex tapes.

For a story being reported around the world, however, it appears to be based on a rather flimsy premise. The Chosun Ilbo, one of the largest newspapers in South Korea, vaguely cited "sources in China" for the report. It has not been confirmed by any other publication.

Some of those who watch North Korean news see the report as suspect. "These rumors start with unnamed and unverified sources in the South Korean media and, for the most part, they're not true (and impossible to prove)," Chad O'Carroll of North Korean-watching website NK News told Business Insider. "They usually turn out to be wrong a few months later by which point no one has noticed and everyone has forgotten the story anyway."

"I don't trust these sources," says Steven Herman, formerly Voice of America's Korea correspondent. "Even mainstream media in South Korea has repeatedly been wrong on these sensationalistic stories originating from the North."

Barbara Denmick, Beijing correspondent for the Los Angeles Times and author of "Nothing to Envy: Ordinary Lives in North Korea," says she has no idea if the report is true. "Chosun Ilbo isn't bad," she added, "but it is hard to trust this stuff. A lot of deliberate misinformation out there."

It's not the first time that a story that appears to show a theatrical brutality in Kim Jong-un's regime has made headlines worldwide. Last year there were also reports that Kim Jong-un personally ordered the execution of an army minister by "mortar round" — which seems to be an elaborate and ultimately pointless method for execution.

That story was sourced, again, back to the Chosun Ilbo, which said the information was from a "South Korean government source." That struck some as suspect. Mike Madden of North Korea Leadership Watch blog wrote an essay for Foreign Policy magazine that concluded that the execution was possible but ultimately impossible to verify.

"You've got to remember that a lot of the time the source is South Korean and it's in their interest to distort or perhaps weave the truth every now and then," O'Carroll says when talking about the mortar round story.

Part of the issue is simply a lack of information. North Korea is a fascinating place that people are very interested in, but it's also a very closed society. Few foreign journalists work inside North Korea. The Associated Press is the only Western new organizations with a bureau there, Chinese and Russian news agencies are constrained by their own government's policies censorship, and North Korea's official news outlets rarely, if ever, feature anything but state-sanctioned propaganda.

One of the few places to fill this void in North Korean news is South Korea — a country that has been technically at war with the North since the 1950s. South Korean reporters aren't exactly welcome in the North, so many of these stories rely on ROK government officials, sources in China, and North Korean defectors.

Andray Abrahamian , a Executive Director of Choson Exchange, a Singaporean non-profit providing training in business, economic policy and law to young North Koreans, says that the Choson Ilbo is a conservative paper with close ties to the South Korean state. "That is a state that is still in a battle for legitimacy for control of the Korean peninsula with a competing government," he adds.

Abrahamian wrote an article for NK News that pointed to a number of bizarre rumors about North Korea, many of which began life in the South Korean press.

NK News' O'Carrell is able to point to two other important stories that appeared to come directly from ROK:

[There's] the alleged coup attempt the Choson Ilbo spoke about a few months ago. There was, according to yet another unnamed source, a firefight in central Pyongyang (no-one working there reported anything and central Pyongyang is not a big place!). There's also the Musudan missile "raising" nonsense that was going on towards the end of this years tensions. The source, every time, was the ROK MoD [Ministry of Defense]. When they said jump, Yonhap printed it and global media, well, jumped.