MYRA Hindley was given an official warning about her ability to mimic the voices of prison staff which they feared might have enabled her to get electronic door locks opened.

Papers released through the National Archive reveal this and other insights into the Moors Murderer's time behind bars.

They also show that she came into conflict with jail bosses after her right to have a vegetarian diet was withdrawn when someone spotted her being given a piece of bacon at breakfast.

In a handwritten letter on A4 prison notepaper she launches into a lengthy, wordy, self obsessed two-page plea to have her vegetarian privileges restored.

Dated September 22 1978, the letter to the governor of Durham Prison says: "It wasn't alleged that I had been seen eating the bacon, merely that it was known I was the recipient of it. This in fact is not true, as I pointed out. I was the recipient of a piece of fried bread, not the bacon, which I don't eat because I don't like it. So I was taken off my diet on the basis of allegedly receiving a piece of bacon which nobody saw me eating.

"I booked for the doctor yesterday to ask him to reinstate the vegetarian diet, which he refused to do. I told him that I hadn't eaten the bacon, that on one occasion [i had] eaten a corned beef sandwich, and on the basis of one `lapse', I feel it is unfair, and a drastic measure, to remove me from a diet I have been on since 1969.

"Alien food"

"He said he wasn't interested in 1969, but now, and I asked if he was aware that by putting me on an ordinary diet, he wasn't condemning me to alien food for a matter of months or even a couple of years but for an unlimited, indefinite period of time."

She adds: "When I came into prison I was on an ordinary diet, and after some time it was noted that I ate very little meat and had lost weight and become run-down. The doctor suggested I go on a vegetarian diet, where at least I would be getting protein, etc, from cheese and eggs.

"Since 1969 I have been listed as a vegetarian diet and a raw-veg diet. I did on occasion eat meat, as it was know I wasn't a `true' vegetarian, but basically my diet has been vegetarian."

In a later and similarly self-obsessed and lengthy letter to the deputy governor she argues she should be given sick pay because she cannot work after being injured.

The details of her injury are blacked-out, but she talks of pain walking and says it looks likely to make it impossible for her to "get over to the workroom" for between four and six months.

Dated September 1 1982 she says in the letter, "unfortunately I have a very low pain threshold" and adds: "This is why I wanted to see whether something could be done about a `sick pay' wage, perhaps a `related earnings' scheme introduced; ie a balance between basic pay (which is also punishment pay) and what one was earning before being hospitalised."

Manipulate

Internal memos from prison staff reveal she is also thought to be trying to manipulate the system to her own ends and get preferential treatment.

A note written in November 1975 when Hindley was in Holloway states: "I wish to bring to your attention that the staff on F wing feel that Myra Hindley is manipulating the Education Department.

Other notes reveal she says she does not want to attend the funeral of her sister Maureen in 1980.

In a letter dated 11/7/80 she says: "I have been asked if I wish to attend the funeral of my sister, Maureen.

"I wish to state that I do not want to be there. I do want to attend the funeral and share my family's sorrow, but I feel I would only add to it if the press or other media are present, which I'm sure they will be. So I have decided not to ask to go for that reason - to protect my family and my sister's dignity."

She also writes to say that after being informed her father had died on November 7 1980 she does not want to go to the funeral. She does not give a reason why.