ABOARD A US MILITARY AIRCRAFT - On his way to visit Bagram Air Base in Afghanistan, Secretary of Defense Chuck Hagel praised the special military operation that extracted Sgt. Bowe Bergdahl, a nearly five-year prisoner of war, from his Taliban captors.

"This is a very happy day for the Bergdahl family," Hagel said.

Saturday evening Jodi and Bob Bergdahl appeared with President Barack Obama in the Rose Garden as he announced the successful mission. A U.S. official said Bergdahl hasn't yet spoken with his parents.

The operation, which transpired peacefully, was weeks in the making, with most of the negotiating occurring between the government of the Gulf nation of Qatar and the Taliban who held Bergdahl.

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Day of communication was between the commander of the Special Forces team and the Taliban leader on the ground.

Although Bergdahl had spent most of his captivity in Pakistan, the recovery mission took place in Eastern Afghanistan, a senior Defense official said.

In exchange for Bergdahl's return, the United States released five detainees from the Guantanamo Bay prison to the custody of the Qatari government, which pledged to bar the men from traveling for a year after their release.

Hagel said the operation took place just in time, as Bergdahl's health had been deteriorating. Bergdahl also is having trouble speaking English, as his father noted during President Obama's address.

"It was our judgment that if we could find an opening and move very quickly with that opening, that we needed to get him out of there essentially to save his life," Hagel said.

(Credit: U.S. Army/AP Photo)

Bergdahl is currently receiving medical treatment at Landstuhl Medical Center in Germany.

"The Landstuhl staff is sensitive to what Sgt. Bergdahl has been through and will proceed with his reintegration at a pace with which he is comfortable," read a statement from the medical center.

When Bergdahl is well enough he will likely be moved to Brooke Medical Center in San Antonio, Texas.

It had been suggested that Bergdahl abandoned his post, but Hagel on Sunday said there would be no immediate punishment or efforts to determine why he was off base.

"Sgt. Bergdahl is a member of the U.S. army. Our first priority is assuring his well-being and his health and getting him reunited with his family. Other circumstances that may develop, they will be dealt with later," Hagel said.