Story highlights Kenneth Bae's sister asks North Korean authorities to have mercy

U.S. says Swedish reps have visited the three detained Americans since June

All three men said they have signed statements admitting guilt

North Korea monitors the interviews of Bae, Matthew Miller and Jeffrey Fowle

Three Americans detained in North Korea spoke out about their conditions and pleaded for U.S. help in interviews with CNN.

Kenneth Bae, Matthew Todd Miller and Jeffrey Edward Fowle were presented to CNN's Will Ripley at a Pyongyang hotel Monday. Each was given five minutes for an interview.

All three men said they hope the U.S. government will send an envoy to North Korea to help get them out of their situations, similar to how former President Bill Clinton helped secure the release of two journalists in 2009.

Bae, who is serving a 15-year prison sentence for "hostile acts to bring down its government," said he is working eight hours a day, six days a week at a labor camp.

North Korea claimed Bae was part of a Christian plot to overthrow the regime.

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"Right now what I can say to my friends and family is, continue to pray for me," he said.

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Despite what he called "hard labor," Bae said he has been treated "as humanely as possible."

Miller, who is accused of tearing up his tourist visa and seeking asylum upon entry, implored the U.S. government for help during his interview.

He said he wanted to tell the United States that "my situation is very urgent, that very soon I am going to trial, and I would directly be sent to prison."

He said he will not learn of his charges until he goes to trial.

Fowle, an American tourist accused of leaving a Bible in a hotel where he was staying, said he has "no complaints" about his treatment.

"It's been very good so far, and I hope and pray that it continues, while I'm here two more days or two more decades," he said.

All three men said they have signed statements admitting their guilt. North Korean officials monitored and recorded all three interviews, and CNN was unable to assess independently the conditions under which the men were being held.

U.S. National Security Council spokesman Patrick Ventrell said Monday that securing the Americans' release "is a top priority and we have followed these cases closely in the White House. We continue to do all we can to secure their earliest possible release."

State Department spokeswoman Jen Psaki said, "There is no greater priority for us than the welfare and safety of U.S. citizens abroad.

"Out of humanitarian concern for Jeffrey Fowle, Matthew Miller, and their families, we request the DPRK release them so they may return home," Psaki said, using the initials for North Korea's official name, the Democratic People's Republic of Korea. "We also request the DPRK pardon Kenneth Bae and grant him special amnesty and immediate release so he may reunite with his family and seek medical care. We continue to work actively to secure these three U.S. citizens' release."

The Swedish Embassy in Pyongyang acts as the "protecting power for issues involving U.S. citizens in North Korea," and the United States is in "regular, close coordination" with the embassy, she said. Swedish representatives visited Fowle on June 20, Miller on May 9 and June 21, and Bae 12 times since his detention, most recently on August 11 in a labor camp, Psaki said.

Surprise meetings

The circumstances leading up to the CNN interviews were bizarre.

A CNN team was on a government tour about two hours outside Pyongyang when it learned it had to leave immediately to meet with a high-level government official in the capital.

The crew boarded a van to a secret location, where it found out the meeting was with the three Americans.

Bae's family has been pushing for his release due to his worsening health. The 46-year-old suffers from diabetes and high blood pressure and has kidney stones.

"I've been going back and forth between hospital and to the labor camp for the last year and a half," Bae told Ripley on Monday.

He said his health has "been failing" over the past 1½ months.

"My hands are numb and tingling, and it's difficult sleeping at night, and I was working in the field every day," Bae said.

U.S. officials have repeatedly called on North Korea to release Bae but to no avail.

Terri Chung, Bae's sister, told CNN on Monday the video was "really difficult to watch" because her brother is generally "full of life and very cheerful. ... It is clear from the video that he is under a lot of stress. And he talks about his health failing and being in complete isolation for almost two years. And it is devastating for our family to see that on TV."

But she told "New Day" that "I think he's doing the best he can. ... Two years of being isolated and working in a labor camp, I know it is not easy. So I think you can see it is taking a toll both physically and mentally."

The U.S. government has been working "behind the scenes to try to procure his release, and we are once again reiterating our thanks, but also too pleading with our government to continue their efforts to secure his release immediately," she added, describing her brother as a "hardworking father of three."

Chung later released a statement asking the North Korean authorities to have mercy.

"It is in your power to release my brother. You could do it today. Please do so. He has confessed to the crimes for which he has been charged, and he has served a longer detainment than any other American since the war," Chung said.

Miller: 'I deliberately committed my crime'

Dressed in a black turtleneck and often staring at the ground in his interview, Miller said he has admitted his guilt -- even though he won't learn of his charges until he goes to trial.

"But I will say that I prepared to violate the law of the DPRK before coming here," Miller said.

"And I deliberately committed my crime. I have already admitted my guilt and apologized to the government of the DPRK and I have been asking for forgiveness."

When asked why he reportedly sought asylum in North Korea, Miller said he already discussed his motive during his investigation and that "for the interview, it is not necessary."

He expressed frustration that "there's been no movement from my government."

"The American government is known for having a strong policy of protecting its citizens, yet for my case there is still no movement," he said.

Fowle describes 'desperate situation'

North Korea announced Fowle's detention in June, saying he had violated the law by acting "contrary to the purpose of tourism."

"The charges are violations of DPRK law, which stems from me trying to leave a Bible," the 56-year-old told Ripley.

"It's a covert act and a violation of tourists rules. I've admitted my guilt to the government and signed a statement to that effect and requested forgiveness from the people and the government of the DPRK."

Fowle said he expects his trial to start within a month.

"You guys should convey my desperate situation," he said.

"I've got a wife and three elementary school-aged kids that depend on me for support."