I see torture every single day - jailed Irish man
Dubliner Ibrahim Halawa has spoken of how he witnesses torture every day inside an Egyptian prison.
In a letter smuggled out of the jail, he wrote about "men covered in honey and tied to trees so they are attacked by insects". Two other brutal methods used are electrocution and assault with machine guns.
Mr Halawa (20) has been imprisoned in the North African country for almost three years since he was arrested during political protests while on holidays in Cairo with his sisters.
He is currently awaiting trial and a potential death penalty.
In the letter, Mr Halawa describes the physical and sexual torture of inmates in the Wadi el-Natrun prison.
He said fellow inmates are forced to watch each other endure torture methods that include being beaten with plastic pipes, electrocuted, assaulted with machine guns and put on 'the sweeper' - a torture method that involves tying inmates to a plank and leaving them to hang as if they are on a spit.
According to the letter, published in UK newspaper 'The Times', men are also covered in honey and tied to trees so they are attacked by insects.
Mr Halawa wrote: "They crucify men. They hold a man's arm against the curb and you hear it break when they kick it."
He said he wakes up every day to the "screams of prisoners being tortured".
In a letter to his family last month, the former Dublin schoolboy said the 1,000 days he had spent in prison had felt like 1,000 years.
He told of how other prisoners had taken their own lives.
"One thousand days with 1,000 different stories. Sadly not the type of joy, laughter and smiles. But rather the type full of suffering, pain, torture, tears, abuse, suicide and death," he wrote.
Mr Halawa's sisters are calling for more assertive action to free their brother.
Amnesty International's director Colm O'Gorman said the organisation conducted a review of the prosecution evidence and concluded that Mr Halawa could not have committed the crimes with which he has been charged.
His mass trial has been delayed 13 times and is now due to take place on June 29.
The Department of Foreign Affairs said every effort was being made to secure his release.