A 'dangerous' 20-year-old who shot two dogs and stabbed two people kept 'chilling' notebooks about killing and dismembering people, a court heard.

Kerney Grantham ventured out onto Mousehold Heath in Norwich - a popular area for dog walkers- with an air rifle and hunting knife.

He seriously injured one dog after shooting it in the abdomen and hurt another when he shot it in the leg.

Police were called and Grantham was arrested with the weapons on him.

But when officers searched his room, they found notebooks which contained 'chilling' drawings that went in graphic detail of the injuries that he wanted to inflict on other people and animals.

Norwich Crown Court heard that after he was remanded in custody, he stabbed two other people with a makeshift knife - including a prison officer who has since suffered post traumatic stress as a result of the incident.

He also admitted to attacking another prisoner with a billiard ball placed inside two socks; striking him in the back of the head.

Grantham, formerly of Yarmouth Road, Norwich, said in interview that he 'felt amazing' after stabbing his victims and had carried out the attacks so others knew he was 'not to be messed with' and 'wanted to inflict pain'.

Sentencing Grantham to an extended sentence of six years youth custody with a five year licence period, Judge Stephen Holt said the case was 'deeply worrying'.

He said: 'It seems to me this series of criminal offences is about as worrying as it can get from someone your age.

'I do find you to be a dangerous defendant who has to be sentenced in such a way.'

Referring to the notebooks Judge Holt found in the defendant's room which he described as 'chilling', he said: 'It's quite clear that you wanted to inflict pain on both animals and people. The drawings set out in graphic detail the sort of injuries you wanted to inflict on fellow human beings.'

A psychiatric report concluded that Grantham was not suffering from a mental illness but committed these acts because he 'enjoyed doing it'.

He told doctors that he 'enjoyed causing pain' and that 'killing animals felt good', adding that he was working up to killing people.

Grantham, who wore a grey sweater and appeared to be grinning throughout the hearing, had previously admitted to two counts of wounding, two counts of causing unnecessary suffering to an animal, assault occasioning actual bodily harm (ABH), possession of a loaded weapon in a public place and possession of a bladed article.

Grantham was initially arrested following the dog shooting incidents on Mousehold Heath on December 10 last year.

The other offences happened in prison with the two counts of wounding taking place on December 21 last year, and the ABH on March 4 this year.

Michael Clare, mitigating, conceded that this case was more serious than the sentencing guidelines envisaged, but urged the judge to give consideration to the injuries which were actually caused which, luckily, were comparatively minor.

He said Grantham deserved credit for plea and was still only 20.

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