A convicted terrorist has been jailed for four years for "calmly" attacking another prisoner with boiling oil at a high security prison.

Omar Khyam, of Langley Walk, Crawley, blamed an "atmosphere of fear" at his high security prison for the attack.

He scalded armed robber Malcolm Cruddas on October 17 last year at Frankland Prison, Durham.

The 26-year-old, who pleaded guilty to grievous bodily harm with intent, is currently serving a life sentence for his part in plotting a series of fertiliser bomb attacks in the south of England.

Christopher Knox, prosecuting, told Teesside Crown Court that Khyam had wanted to be moved from the Durham prison from the moment he arrived.

He said: "He made it clear by himself and his solicitors that he did not want to be at Frankland Prison, he wanted to be at a different prison."

Mr Knox said the attack on Cruddas was unprovoked and caused burns to 15% of his body and had resulted in permanent scarring.

He said: "The defendant approached him from behind and calmly poured a steaming liquid over his head which was either oil or a mixture of oil and water."

But Sam Robinson, defending, said Khyam had attacked Cruddas in "excessive self defence", citing other attacks on terrorist inmates at Frankland.

Last July al Qaida plotter Eesa Barot, formerly known as Dhiren Barot, spent five days in hospital after he was scalded at Frankland Prison.

Proceedings against inmate Gary Moody were later dropped at the request of Barot.

Also in July 2007, the jail cell of one of the plotters for the failed July 21 attacks, Hussain Osman, was set alight.

Mr Robinson said: "There was the previous attack on Mr Barot which was of a similar nature and resulted in similar injuries as those being discussed here and the arson attack on Mr Osman so those two incidents, regardless of any actions by the Prison Service, led to an atmosphere of fear and mistrust and a sense of abandonment which was felt by the Muslim community at Frankland at the time."

Khyam was found guilty of plotting to kill hundreds of people by targeting The Ministry of Sound nightclub, Bluewater shopping centre in Kent and the gas network using a giant fertiliser bomb.

He was sentenced to a minimum of 20 years in prison at the Old Bailey in April last year.

After he was sentenced, his wife, whom he married him three days before his arrest, said threats had been made to his life in prison. Khyam is known as the "middle class terrorist". Grandson of a British Army colonel and son of a wealthy businessman, he was brought up in Crawley. As a youngster he adored Manchester United and was captain of his school cricket team.