Who Is the U.S. Soldier Detained in North Korea? All About Alleged Runaway Travis King

King, who was stationed in South Korea, was allegedly seen "running" across the North Korea border shortly before he was set to face discipline by the U.S. military

<p>Facebook/Travis King</p> Travis King

Facebook/Travis King

Travis King

New details are emerging about the American soldier who was detained in North Korea after crossing into the country from South Korea “without authorization" earlier this week.

Pvt. 2nd Class Travis King is now in North Korean custody after running across the border this week, but many lingering questions remain.

Defense Secretary Lloyd Austin told reporters Tuesday that officials are "very early" in the process of determining what, exactly, happened, and that "there's a lot that we're still trying to learn."

"What we do know is that one of our service members who was on a tour, willfully and without authorization crossed the military demarcation line. We believe that he is in DPRK custody," Austin added.

Here's what we know about King so far.

Related: U.S. Soldier Detained in North Korea After Allegedly Crossing the Border to Avoid Disciplinary Actions

He Was Recently Released from a Detention Center in South Korea

King had reportedly been released recently from a South Korean prison, where he was held for two months on assault charges.

Various South Korean media outlets and the Associated Press report that King's imprisonment was the result of allegedly punching a South Korean national in a club last September. The outlets report that in addition to prison time, he was fined nearly $4,000 for allegedly causing public damage by kicking a police car and being uncooperative during his arrest while shouting profanities about Koreans.

The AP reports that King was released from the South Korean prison on July 10 and was set to head to the U.S. to face further military disciplinary action (and, potentially, discharge from the Army).

He Fled the Airport and Joined a Tour Group at the Border Before Deliberately Crossing into North Korea

King was reportedly at the airport on Tuesday afternoon, where he was due to board a flight to a military base in Fort Bliss, ABC News reports. But at some point, it appears he left the building and joined a group of civilians who were on a tour of the nearby Joint Security Area, which separates North and South Korea and is known to be heavily guarded by soldiers from both sides.

At one point, King left the tour group and ran across the border into North Korea, according to reports.

"A U.S. National on a JSA orientation tour crossed, without authorization, the Military Demarcation Line into the Democratic People’s Republic of Korea (DPRK). We believe he is currently in DPRK custody and are working with our KPA counterparts to resolve this incident," the United Nations Command said in a statement Tuesday.

Related: Coroner&#39;s Report for Otto Warmbier Deepens Mystery Surrounding His Death After North Korea Release

Others who were in the same tour group as King told reporters that he allegedly laughed before running full-speed toward the North Korean border.

Speaking to the AP, Sarah Leslie, a tourist from New Zealand who was part of the tour group, claimed the tour was nearly over when she saw a man “running what looked like full gas towards the North Korean side."

The group of civilians was ushered inside while, according to Leslie, South Korean and American military members chased after King, who they were unable to catch up to.

“Everybody was stunned and shocked,” Leslie said. “There were some people who hadn’t even realized what was going on.”

Officials Believe King Is Now in North Korean Custody

White House press secretary Karine Jean-Pierre said Tuesday that U.S. officials "believe the soldier is currently in DPRK custody and are working with our North Korean counterparts to resolve this incident."

The U.S. does not have official relations with North Korea, which the U.S. State Department warns Americans against entering "due to the continuing serious risk of arrest and long term detention of U.S. nationals."

But U.S. officials are now “engaging” South Korean and Swedish officials (who represent U.S. interests in North Korea) on the apparent defection, Jean-Pierre said.

"The White House, the Department of Defense, the State Department, and also the UN are all working together to ascertain more information and resolve this situation," she added. "I don’t have more to share beyond that. We are looking into this. We’re trying to get more information."

She continued: "“Our primary concern at this time is ascertaining his well-being and getting to the bottom of exactly what happened."

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In his own remarks to reporters, Defense Secretary Austin said that the U.S. is "closely monitoring and investigating the situation" and "working to notify the soldier's next of kin" before officially identifying him.

"I'm absolutely foremost concerned about the welfare of our troop," Austin said, "and so we will remain focused on this ... and this will develop in the next several days."

Calls to King's family members were not immediately returned.

His detainment marks the first American detainment in North Korea in nearly five years, the AP reports — the last being University of Virginia student Otto Warmbier, who returned to the U.S. in a coma and died soon afterward.

The detainment also comes at a time of heightened tension between the U.S. and North Korea, which has been testing ballistic missiles in a move that's alarmed Western officials.

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