A CHILD rapist who once threatened to blow up Prime Minister Theresa May has been jailed for making more hoax bomb threats against prison staff, including the governor.

Paedophile Marcia Walker, a transgender prisoner previously known as Mark Walker, made three hoax bomb threats while in custody at HMP Long Lartin, a high security prison in South Littleton, near Evesham.

The 43-year-old had previously been jailed for six months for claiming there was a bomb at Prime Minister Theresa May's home in November 2012 when she was Home Secretary, telling her in a letter that she was 'a dead woman'.

Walker appeared before his honour Judge Robert Juckes QC to be sentenced for three further hoaxes at Worcester Crown Court on Wednesday.

She had already admitted making a hoax call to Crimestoppers on December 4, 2015 and two written bomb threats to senior prison officer Bernard Thompson and Tom Wheatley, the prison governor, both on January 28 last year.

There was some uncertainty about when Walker was due to be released from her existing sentence although a date in 2020 was suggested.

Judge Juckes said he must extend Walker’s sentence to deter Walker from making further disruptive threats.

Judge Juckes said: “You have spent much of this century in custody for the most serious kind of offences against children.

"Whilst in custody, in order to draw attention to yourself and for other reasons outlined by the probation service and a psychologist, you have taken to making threats that bombs will be planted and will explode.”

He said Walker's grudge arose because she wanted transgender surgery, the possibility of which was still being investigated.

The judge said: “There is apparently no other way of controlling your behaviour other than by making it clear to you that each time choose – and it is your choice – to behave in this way, you face a longer sentence.

"The only person that can end this cycle is you."

Charles Hamer, prosecuting, said Mr Thompson, a senior prison officer with 24 years’ experience, had been handed a piece of paper by another officer from Walker which said a bomb was due to explode at his home that night.

Mr Hamer said: “He was concerned for the risk to his wife.”

An hour later a second piece of paper from Walker was brought to the attention of the wing officer which made reference to a threat to the governor, Tom Wheatley.

The letter said an incendiary device had been sent to the governor’s home and Walker said she looked forward to watching what happened on television.

Mr Wheatley said the public were unlikely to be directly aware of the operational impact of such threats but that the prison contained convicted terrorists and Walker’s threats must be considered against that background.

Walker has five convictions for 38 previous convictions and was sentenced to 13 years at Canterbury Crown Court on January 17, 2003.

The prison sentence was imposed for two rapes against girls under the age of 16, one aged just four as well as 10 counts of making indecent photographs of children, seven of taking indecent photographs of children and two of distributing indecent photographs of children.

Walker also made bomb threats while serving at HMP Parkhurst on the Isle of Wight, calling Crimestoppers to claim there was a nail bomb in the prison car park and a bomb at the governor's home address for which he was sentenced to four years on July 6, 2015.

She also previously left answering phone messages saying there was a bomb at a probation hostel in Windsor for which she was jailed for six years at Oxford Crown Court on June 17, 2013.

Simon Worlock, defending, said: "This is a disturbed individual who has been classically institutionalised."

He also stressed that nothing had actually been sent to anyone's address and that 'all he did was make foolish claims'.

Mr Worlock said Walker had been assessed as having Asperger's syndrome with rigid thinking, a lack of insight and a fixation on blaming the prison service.

He said the offences were 'a nuisance' but 'not top end' in terms of sentencing and noted that at the time of the arrest police did not believe he had the means to arrange for the threats to be carried out.

Mr Worlock added: "He doesn't know where the governor lives."

The judge sentence her to an extra five years in prison once she has served her existing sentence.