South Korean soldiers stand guard on Unification Bridge. Representatives from North and South Korea held a second day of marathon talks Sunday. (Ahn Young-Joon/AP)

Representatives from North and South Korea held a day of marathon talks Sunday — stretching more than 21 hours past noon local time Monday, without any word of either progress or failure — as they tried to find a way to defuse escalating tensions. 

But even as the talks continued, the South reported that more than 50 submarines from the North appeared to have left their bases and that troop numbers had been doubled on the northern side of the demilitarized zone that separates the estranged neighbors. Meanwhile, South Korea brought six fighter jets home early from drills in Alaska.

Still, the fact that the talks were continuing was positive, analysts said.

“The fact that they’re still at the table is a somewhat hopeful sign,” said Evans Revere, a former U.S. diplomat with long experience dealing with both Koreas. “The context in which it has all unfolded is obviously a troubling one, particularly reports of North Korean military movements. They’re usually indicators that they’re getting ready for a fight.”

The two sides met for 10 hours Saturday, until almost dawn Sunday, then resumed at 3 p.m. Seoul time. They were still going at 8 a.m. Monday.

The South Korean army's multiple rocket launch systems are deployed in Yeoncheon, south of the demilitarized zone that divides the two Koreas. (Ahn Young-Joon/AP)

The South is represented by its unification minister, Hong Yong-pyo, and national security adviser Kim Kwan-jin, while the North sent Kim Yang Gon, director of the United Front Department, and Hwang Pyong So, director of the general political bureau of the North Korean army. Analysts said it was significant that Hwang was there, because he is considered to be leader Kim Jong Un’s deputy.

Epic rounds of talks between the two Koreas are not uncommon — they embarked on a similar marathon effort last year after a shooting episode on the border — and neither are belligerent threats from Pyongyang.

But the current bluster had many analysts warning of the potential for miscalculation, not least because the tensions coincided with annual drills that had 80,000 troops, led by the South Korean and American militaries, simulating their response to a North Korean attack.

The current tensions began this month with a land mine attack that severely injured two South Korean soldiers in the demilitarized zone (DMZ).

South Korea responded by resuming “psychological warfare” operations — installing speakers in the DMZ to blast news and pop music across to North Koreans and disrupting the regime’s efforts to keep its citizens isolated.

North Korea shot several rockets at the speakers Thursday, prompting the South to retaliate with a volley of howitzer rounds. Then Pyongyang gave Seoul a deadline of 5 p.m. local time Saturday to dismantle the speakers or face military action, but the South made it clear that it would not.

Instead, they agreed to talk.

The question now, for both sides, is how they de-escalate the situation without “losing face,” an important consideration in Asia generally but especially for the rival Koreas, each seeking to assert the supremacy of their system.

Neither government has divulged the content of the talks.

“South Korea wants an apology for the mine attack, and the North Koreans in return want the broadcasts to be stopped,” said James Kim of the Asan Institute for Policy Studies in Seoul. But he said it is unlikely that the talks will be productive until the joint military exercises end Friday.

“If you think about it from the North Korean point of view, they don’t have much leverage in terms of what they could to do pressure South Korea,” Kim said. “So it’s understandable why they’re building up their military presence and playing a cat-and-mouse game with their submarines. The only weapon they have is the element of surprise, and they’re using it right now. Maybe because they truly feel threatened or maybe because they want to get some leverage.”

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