A KNIFEPOINT robber, who once said he felt "aroused" while committing crime, attacked a prison officer when he was asked to turn his cell radio down.
Kevin Marrs, 31, who was jailed for carrying out three robberies in five hours, lunged himself at HM Prison Everthorpe officer Steven Haigh after refusing to turn down music blasting from his radio speakers.
Mr Haigh suffered a chipped tooth and bruising to his arm and wrist after Marrs flipped on May 15 last year.
Marrs pleaded guilty to assault occasioning actual bodily harm.
Prosecutor Philip Evans desc- ribed to Hull Crown Court Marrs' response to being asked to turn the music down.
"The defendant replied, 'F*** off, what will you do', said Mr Evans. "It led to the decision to remove the defendant's radio.
"The defendant was adapting an aggressive posture in the middle of the cell and, when asked to move back, he refused and then lunged at Mr Haigh.
"He put his hand up to try to stop the defendant getting nearer, but the defendant, who is taller and heavier, crashed into Mr Haigh, forcing him back."
Mr Haigh tried to force Marrs' head down, but he lashed back, shouting, 'F*** off, I'm having you!', the court was told.
Marrs then bent Mr Haigh's arm around until other officers intervene.
He was escorted in handcuffs to a segregated unit, where he remained for three weeks.
A few days after the attack, the crown of one of Mr Haigh's front teeth fell off as a result of him being hit in the face.
He also suffered scratches and bruises.
Pamela Coxon, mitigating, said her client had been having a "bad day" when he attacked Mr Haigh.
Marrs, who is registered with the multi-agency public protection arrangements, a group of authorities responsible for managing sex offenders and violent criminals, was jailed in 2011 for a series of robberies in Wakefield city centre.
During one robbery, he placed one of his victims in a headlock before holding a knife to the back of his neck.
The man was then forced to hand over his wallet and mobile phone.
A psychiatric report described Marrs as presenting a significant future risk to the public after he admitted being aroused by committing robberies.
He was due for release on December 4, after serving half his prison sentence.
Sentencing Marrs to a further nine months in prison, Recorder Peter Babbs said: "Anybody who works in the public sector – and prison officers are at the forefront of that – will receive the protection of the court."
