North Korea's Korean Workers' Party celebrated its 69th anniversary Friday with no early sign that "missing" leader Kim Jong-Un might finally resurface after more than a month out of the public eye.

Kim's unexplained absence has fed a cycle of rumor and wild speculation.

Competing theories range widely from an extended rest period to a leadership coup, via a long list of possible illnesses and ailments including broken ankles, gout and diabetes.

Should he fail to put in any appearance on Friday, the rumor mill is likely to shift up several gears.

North Korea has more than its fair share of political anniversaries, but the Korean Workers' Party anniversary is one of the bigger ones, and Kim would be expected to show up.

For the past two years, he has marked the occasion with a post-midnight visit -- along with other top leaders -- to the mausoleum in Pyongyang that houses the bodies of his father Kim Jong-Il and grandfather Kim Il-Sung.

The North's official KCNA news agency usually reports the event early in the morning, but as of 9:00 am (0001 GMT) there was no mention of any visit.

"My own feeling is that there has been a health problem, but not a particularly serious one," said Chung Young-Chul, a professor of North Korean studies at Sogang University in Seoul.

"A no-show on Friday would certainly force us to consider the possibility that it's more serious than we thought," Chung said.

Mixed messages on health

What little light North Korea has deemed necessary to shed on the situation has only added to the confusion.

North Korean media alluded at one point to the leader's "discomfort", but one member of a top-level North delegation that visited South Korea last week insisted Kim had no health problem at all.

The uncertainty means that every move or comment by North Korea is now seen through the unreliable prism of what it might say about Kim's situation.

Some saw the surprise visit by the high-ranking delegation as a message that all was fine and normal in Pyongyang.

Others saw the presence of Kim's de-facto number two in the delegation as further evidence that the leader may have been sidelined or pushed out altogether.

It is by no means unprecedented for a North Korean leader to drop out of the public eye for a while.

But it is more noticeable with Kim, who has maintained a particularly pervasive media presence since coming to power after the death of his father Kim Jong-Il in 2011.

"He certainly doesn't want to be seen while he is sick and looking weak," said Bruce Bennett, a senior defence analyst with the RAND corporation.

"Looking weak is not good for a North Korean leader who is trying to maintain control," Bennett said.

Although he has not been seen since he attended a musical concert with his wife on September 3, Kim's name has not disappeared from the local media.

And while he did not join other senior leaders at the unveiling last week of two new giant statues of his father and grandfather Kim Il-Sung, a floral tribute bearing Kim Jong-Un's name was prominently displayed.

The South Korean government has largely avoided playing the guessing-game.

In a meeting Tuesday with legislators, Defence Minister Han Min-Koo reportedly cited intelligence sources saying Kim was staying at a "certain place north of Pyongyang" but offered no other details.