An Australian incarcerated in the US military camp at Guantanamo Bay on terror charges has told his family that he is on the brink of madness.
David Hicks has been in Guantanamo Bay since 2001
"I feel as though I am teetering on the edge of losing my sanity," wrote David Hicks in a letter dated in August but only recently received by his family.
He wrote of confusion and mood swings brought on by his detention.
Mr Hicks, 29, made his second appearance before the military tribunal at Guantanamo Bay on Monday.
His lawyers are arguing that his military trial, scheduled for 10 January, should be dropped. The charges against him include conspiracy to commit war crimes, attempted murder and helping the enemy during the 2001 US-led war in Afghanistan.
"I feel as though I'm teetering on the edge of losing my sanity after such a long ordeal, the last year of it being in isolation," Mr Hicks wrote to his father.
"I've reached the point where I'm highly confused and lost, overwhelmed if you like. I suffer extreme mood swings every half hour, going from one extreme to another," he continued.
"The decisions I'm making, which are no doubt important, are often done without thought or sometimes care. All decisions are made in chains, including being chained to the floor."
There have been widespread reports of routine harsh treatment at Guantanamo, including isolation from the outside world, the use of bright lights and loud music, and limited exercise.
But Mr Hicks' family were surprised to receive the letter as previous correspondence from their son has been heavily censored by the US military authorities.
"Depression seems to be their preferred order of the day," wrote Mr Hicks. "I spend an average of 350 hours by myself between brief visits. No doubt this situation has negative psychological effects which will also permanently scar me."
David Hicks has pleaded innocent to charges brought against him by the US military. The Muslim convert and former abattoir worker faces a maximum of life imprisonment.
He is one of two Australian citizens held at Guantanamo Bay.
The other, Egyptian-born Mamdouh Habib, was arrested in 2001 in Pakistan. His family denies he has any links with al-Qaeda, saying he was captured while looking for a school for his children.