A convicted criminal has admitted killing a prison security officer by kicking her in the head as she was escorting him from his cell following a court appearance.

       Humphrey Burke, 28, who was described as “unpredictable and dangerous”, left Lorraine Barwell, 54, with catastrophic brain injuries when he attacked her at Blackfriars Crown Court in 2015.

       In 2016, he was charged with her murder but was deemed unfit to enter a plea due to mental illness and sent to Broadmoor hospital.

       But during a hearing at the Old Bailey on Thursday, Burke was re-arraigned and admitted manslaughter by grounds of diminished responsibility. He will be sentenced on January 11.

       Ms Barwell, a Serco prison custody officer, had been part of an all-female team transporting Burke from Blackfriars Crown Court following a sentencing hearing on June 29 2015.

       He had already been convicted of two attempted robberies at bookmakers the previous October.

       Following the hearing, Ms Barwell and other members of her team went to the cells to prepare Burke for his journey back to prison.

       He was handcuffed, but – as he was being led from his cell – pretended to faint so his cuffs were removed.

       Three custody officers then attempted to get him to his feet, but he began to struggle and so was cuffed again.

       As he was placed back on his feet, however, he began lashing out with his legs, striking Ms Barwell and causing her to fall to the floor.

       As her colleagues attempted to pull him away, he kicked out again and caught her in the head.

       London Ambulance Service were called and she was rushed to the Royal London Hospital where she remained in a coma for several days.

       She did not regain consciousness and died in the early hours of July 3.

       Speaking at the time, Detective Chief Inspector David Reid of the Homicide and Major Crime Command said:

       “Lorraine Barwell was not a threat to Humphrey Burke; she was merely doing her job – the same job that she had carried out with dedication and professionalism for many years.

       “Burke chose to lash out, using what the pathologist described as severe force to inflict catastrophic injuries on Lorraine.

       “Her death was needless, caused by a senseless act of violence on the part of Burke.”

       During a hearing at the Old Bailey, Burke’s guilty plea to manslaughter on the grounds of diminished responsibility, was accepted by the Crown Prosecution Service.

       He was remanded into custody at the secure hospital where he has been held.