The US soldier released by the Taliban after five years has told military officials that he was tortured, beaten and held in a cage by his captors in Afghanistan after he tried to escape.
Sergeant Bowe Bergdahl is being treated at a US military medical facility in Germany following his release a week ago.
The New York Times has reported that Sgt Bergdahl is not yet emotionally prepared to return to his family.
His release in exchange for five Taliban militants from Guantanamo Bay has ignited a political firestorm and sparked a debate over whether the 28-year-old should be given a hero’s welcome or punished as a deserter from his US base.
His home town abruptly cancelled plans for a welcome-home celebration on Wednesday, citing security concerns.
Hailey, Idaho, a town of 8,000, where Sgt Bergdahl’s parents, Bob and Jani Bergdahl, live, has been swamped with hate mail and angry calls.
FBI spokesman William Facer said: “The FBI continues to monitor the situation in Hailey, Idaho. We are working jointly with our state and local partners and taking each threat seriously.”
Bergdahl went missing on the night of June 30, 2009, near the town of Yahya Kheyl but the circumstances are in dispute.
In a video, Bergdahl stated that he was captured when he fell behind during a patrol. There have been claims he left the base in an attempt to walk to India after becoming disillusioned with the war. The Taliban alleges he was ambushed after becoming drunk off base.
However the US military has denied the Taliban’s claims, and accused his kidnappers of lying in order to create discord among the allied forces.