A prisoner whose single punch left a fellow inmate disabled after he fractured his skull has been jailed for four years.

Convicted robber Nicholas Weatherall, who described himself as someone who "fights like an animal", attacked Kirk Ramsden while they were both in HMP Elmley on the Isle of Sheppey.

The two men had been friends for many years but Weatherall, 39, attacked Mr Ramsden because he believed that while he was behind bars and Mr Ramsden had been on the outside, he had become "more than just friendly" with Weatherall's girlfriend, Zoe Dean.

The force of the punch on March 15 last year knocked Mr Ramsden unconscious and he fell, hitting the back of his head and cracking the skull.

The consequences of his injuries were described at Maidstone Crown Court as "devastating and catastrophic".

Mr Ramsden, who can remember little of the attack itself, has been left with both physical and cognitive impairment.

Weatherall, of no fixed address but formerly from Faversham, denied inflicting grievous bodily harm but was convicted by a jury.

Despite claiming he was not responsible for hitting his former friend, Weatherall admitted carrying a razor blade in the prison in readiness to "cut him open".

He also said he was glad Mr Ramsden had been injured - and after being sentenced Weatherall told a woman in the public gallery he would "have him again" upon his release.

Passing sentence, Judge Martin Joy told Weatherall he had been "waiting for an opportunity" to harm Mr Ramsden.

"You had worked yourself up to some real anger against Mr Ramsden. On a scale of one to 10 you said you were over the top in terms of your feelings," said the judge.

"It has to be recognised that had you been given the opportunity to commit a more serious offence there is little doubt you would have done.

"You gave evidence yourself that you were dangerous and had a propensity for violence. That was a realistic self-assessment by you.

"You are, as you yourself described, a career criminal and you fight like an animal. The court has to recognise that you are a dangerous man."

Weatherall had been jailed in June 2009 for robbery. He was given an indeterminate sentence for public protection (IPP), with a minimum term of five years, less time served on remand.

The court heard he would have been eligible for parole in February next year.

But Judge Joy ordered that the four-year term imposed by him must be served consecutively to the IPP.

Therefore, it will not start until February and Weatherall must serve half before going before the Parole Board.

Weatherall sat slumped in his chair or across the barrier of the dock while Judge Joy passed sentence.

At the end of the hearing he stood and said: "Worth every day, thank you very much," and then, pointing at a woman sitting in the public gallery, added: "I'll have him again when I get out."

The woman later thanked the jury before she left the courtroom.

Charlotte Newell, defending, told the court there was an element of provocation for the attack.

"It was a single blow struck in the context of a person in long-term incarceration with a long-term partner cheating on him with an old friend," she said.

"It is not an excuse but it can be taken into account."

The court heard that the fracture to Mr Ramsden's skull led to breathing difficulties which, in turn, caused a cardiac arrest.

Paramedics used defibrillators and chest compressions on Mr Ramsden for up to an hour at the prison before he was flown by the Kent Air Ambulance to Queen's Hospital in Romford, Essex.

He then spent four days in intensive care and 12 days in the occupational and physiotherapy unit, before being transferred back to Kent.

However, further complications set in and Mr Ramsden required four operations at Guy's Hospital in London to correct a narrowing of his trachea caused by the tubes inserted to help him breath.

Judge Joy said the attack had caused "devastating harm" to Mr Ramsden.

"This man has been left disabled and with very seriously impaired physical and cognitive functions.

"These were catastrophic injuries with a massive effect on the victim."

The jury was told at the start of the week-long trial that the prosecution accepted Weatherall never intended the injuries that were caused, but had acted unlawfully by punching Mr Ramsden.

"This man has been left disabled and with very seriously impaired physical and cognitive functions. These were catastrophic injuries with a massive effect on the victim" - Judge Martin Joy

Prosecutor Alex Rooke said that before Mr Ramsden joined Weatherall at Elmley, there was "some supposition" by Weatherall that his friend had a "more than just friendly" relationship with Miss Dean.

The court was told that after Mr Ramsden had been attacked, Weatherall was overheard by several prison officers saying he had only punched Mr Ramsden once, and that he had been seeing his "missus" for seven months.

However, Weatherall denied making such a comment or hitting Mr Ramsden.

CCTV footage from the prison showed Weatherall near to where Mr Ramsden was punched and getting a paper towel from a dispenser to wipe his hand.

But he later claimed the blood on his fist had been caused by him punching a wall after he became upset during a phone call with his partner.

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