Norwegian mass murderer Anders Behring Breivik accused prison officers of trying to drive him to suicide in conditions he describes as "a mini Abu Ghraib".
Breivik wrote a 27-page letter addressed to prison officials, a copy of which was obtained by journalists.
"If it wasn't for the fact that I am an exceptionally patient person, I would most likely have lost my mind in pure frustration," Breivik said in the letter dated October 15, that was updated on October 26 and October 30. "Anyway, there are limits to what a person can take."
Breivik wrote he is frustrated that guards do not co-operate with his carefully planned daily schedule, where he times his various activities down to the minute.
"One cannot exclude that Ila Prison's leadership has assured itself that 'loyal social democrats' dominate the ward to prevent possibly benevolent people gaining access," Breivik said. He also alleges that the prison director keeps the security regime tight out of personal vengefulness against Breivik.
The 33-year-old right-wing fanatic killed 77 people last year in Norway's worst peacetime massacre. He detonated a car bomb outside government offices in Oslo killing eight people and then drove to the island of Utoya where he massacred 69 members of the Labour Party's youth wing.
Ellen Bjercke, spokeswoman at Ila Prison where Breivik is being held, said the prison had not lifted any security restrictions on Breivik in response to his letter, although he had recently been allowed a normal pen instead of a rubber safety pen, which he had also avidly used during the 10-week trial to make notes.
Breivik said the experience of having to use the stab-free pen was as "an almost indescribable manifestation of sadism".
The self-confessed killer described numerous prison practices as "degrading" in his letter, including that he is watched when swallowing his vitamin pills, that he's not allowed a mop to clean his cell and that he is subjected to daily strip searches, sometimes by female prison guards.
Personal hygiene is also a challenge, he said.
"Use of a toothbrush and electric shaver is always under supervision. One is therefore under mental pressure to finish quickly as the guards are tapping their feet outside the cell ... This limits brushing to once a day and shaving to once a week in order not to have to go through the mental ordeal more often than necessary," he wrote in the letter.
"Therefore there is the likelihood that Norway's own 'mini Abu Ghraib,' in the cellars of Ila Prison, are being kept a secret and that Norway's human rights ambassadors' work to spread the 'world's most humane principles' are avoiding being embarrassed."
Breivik was referring to a prison in Iraq that became notorious in 2004, when photos were released of detainees being abused by US soldiers.
Ms Bjercke said that Breivik was given an electric typewriter earlier this month but that it was not connected to his letter of complaint.
During his pre-trial detention he was allowed a computer that could not be connected to the internet, but it was taken away from him when he started serving his sentence.
The Oslo District Court found Breivik guilty of terrorism and premeditated murder for the July 22, 2011 attacks.
He was given a 21-year prison sentence that can be extended if he's considered a threat.
The self-styled anti-Muslim militant denied criminal guilt, saying he's a commander of a resistance movement aiming to overthrow European governments and replace them with "patriotic" regimes that will deport Muslim immigrants.