Sec. Kerry defends Bergdahl-for-Taliban exchange

(CNN) -- In his first public comments on the issue, Secretary of State John Kerry defended the release of five Taliban figures in exchange for U.S. Army Sgt. Bowe Bergdahl.

Kerry told CNN in an interview that aired Sunday, "I'm not telling you that they don't have some ability at some point to go back and get involved (in fighting). But they also have an ability to get killed doing that."

Bergdahl was released May 31 near the Afghanistan-Pakistan border in an exchange for five Taliban detainees held at Guantanamo Bay, Cuba.

"I don't think anybody should doubt the capacity of the United States of America to protect Americans," Kerry said while in France to commemorate the 70th anniversary of the 1944 D-Day landings.

Kerry told CNN that the former detainees will be monitored closely, and by more people than officials in Qatar, where they were flown after being released. The United States is confidant the conditions of their release will be honored, he said.

"And if they're violated, then we have the ability to be able to do things," he said, without elaborating.

Republican critics in Washington have complained that the exchange for Bergdahl gave up hardened terrorists capable of attacking U.S. troops and interests. In addition, legislators from both parties accuse the Obama administration of violating the National Defense Authorization Act by failing to provide 30 days' advance notice to Congress of a transfer of Guantanamo detainees.

Administration officials have given several reasons for the lack of notification -- a need to move quickly due to Bergdahl's poor health and the overall threat to his safety, and the likelihood that even a small leak of the plan could have led to his death.

New information about Bergdahl's health

Bergdahl is recovering at a U.S. military hospital in Germany as details slowly emerge about his condition after five years of captivity.

Citing an American official, The New York Times reported Sunday that Bergdahl told medical staff that the box he was kept in for weeks at a time was pitch black and like a shark cage.

Army Sgt. Bowe Bergdahl(Photo: U.S. Army)

CNN reported Friday that Bergdahl has said he was kept in a small box after trying to escape, according to a senior U.S. official, who spoke on condition of not being identified. The official also told CNN that Bergdahl suffers from psychological trauma caused by physical abuse.

Doctors at Landstuhl Regional Medical Center, where Bergdahl was taken after his handover, said Friday that he was in stable condition and continued to improve but wasn't ready to travel to the United States.

"There is no predetermined timeline for Sgt. Bergdahl's recovery process," a hospital statement said. "The duration will continue to be based on the pace of his healing and reintegration process."

The Times report added that Bergdahl has taken walks outside his hospital room while wearing his Army uniform, according to the American official. Bergdahl, who was promoted twice on schedule while in captivity, objects to being called sergeant, the Times reported.

Bergdahl was a private first class when he went missing on June 30, 2009, in Afghanistan's Paktika province, where he was deployed with the 1st Battalion, 501st Infantry Regiment, 4th Brigade Combat Team, 25th Infantry Division.

When he is ready, Bergdahl will be flown to the San Antonio Military Medical Center in Texas, where he may be able to reunite with his parents. Bergdahl has yet to speak with them since his release.

Taliban celebrates

Nine songs celebrating the release of the five Taliban detainees were posted to a Taliban website Saturday.

On one tune, a singer calls the men "grand champions" and praises their Islamic faith.

According to a CNN translation, a man sings in Pashto:

Welcome a hundred times, welcome grand champions

Congratulations your new life, O freed men

Welcome a hundred times, welcome grand champions

Congratulations your new life, O freed men

Threats against parents

The FBI is investigating threats against the Bergdahl's parents, who have not been seen publicly since sending their son messages of love through a news conference days after his release.

"We are working jointly with our state and local partners and taking each threat seriously," FBI Special Agent William Facer told CNN in an e-mail Saturday.

Facer declined to detail the nature and severity of the threats, and a military representative for the Bergdahls declined to comment.

Since Bergdahl's release, critics, including a former member of his unit, have contended that Bergdahl deserted. The Army concluded in a 2009 report that he left his post deliberately. But the Army has no definitive finding that Bergdahl deserted because that would require knowing his intent -- something Army officials can't learn without talking to the soldier, a U.S. military official told CNN.

CNN's Barbara Starr, Qadir Sediqi, Ed Lavandera and Devon Sayers contributed to this report.

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