Two Americans freed by North Korea arrive back in U.S.

(CNN) -- Two Americans who spent months imprisoned in North Korea arrived back on U.S. soil late Saturday after the secretive nation's leader, Kim Jong Un, ordered their release.

A plane carrying Kenneth Bae and Matthew Todd Miller, the last two American citizens known to be held by North Korea, landed at Joint Base Lewis-McChord in Washington state.

The pair were released after Director of National Intelligence James Clapper went to Pyongyang as an envoy of President Barack Obama, a senior State Department official told CNN.

Clapper delivered a letter from Obama, addressed to North Korean leader Kim Jong Un, describing Clapper as \"his personal envoy\" to bring the Americans home, a senior administration official told CNN on Saturday.

The letter was \"short and to the point,\" the official said. Clapper did not meet with Kim.

Clapper had no guarantee he would bring the Americans home, a senior State Department official told CNN.

The North Korean government issued a statement about the release, saying it received an \"earnest apology\" from Obama for the men's actions. It also said the two were \"sincerely repentant of their crimes and (were) behaving themselves while serving their terms.\"

According to the statement, the first chairman of North Korea's National Defense Commission ordered the release. The title is one of several top positions that Kim holds in the North Koran hierarchy.

CNN's Will Ripley, Steve Almasy, Barbara Starr, Elise Labott, Jim Acosta, Evan Perez, Ray Sanchez and Michael Martinez contributed to this report.

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