A teenager stabbed a boy with a kitchen knife after the balaclava he was wearing was pulled off. He and another teen had committed a series of armed robberies in Cardiff city centre.

A 15-year-old boy and a 14-year-old boy approached another group of teenagers near the BBC building in Central Square at around 6.20pm on July 3 last year. Both were dressed in black clothing and wearing balaclavas.

A sentencing hearing at Cardiff Crown Court on Friday heard the defendants gestured to a boy who walked up to them. He could see the 15-year-old had a rucksack in his lap and was holding one of his hands inside it.

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Prosecutor Emma Harris said the 15-year-old could be seen holding the handle of a knife, and asked the boy how much money he had on him. The boy told the defendant he had £25 and the 15-year-old said: "Give me the money now". The money was handed over and passed to the 14-year-old. Both defendants then got up and walked away, pursued by the victim who asked for his money back.

The 14-year-old turned round and said: “You ain’t getting the money back”. They started to goad the victim into getting the money back, but walked towards Westgate Street shortly later.

The defendants approached two men waiting at a bus stop near the WRU shop on Westgate Street, and sat next to them. the 15-year-old asked one of the men how much his watch was worth, and asked him what he had in his pockets.

They asked the two men to go to a cashpoint and withdraw money, but they refused. The 15-year-old told the men to hand over their vapes, and said: “Hurry up or I’ll back out my knife”. The two men complied, fearing they would be stabbed if they didn't.

Upon the defendants returning to Central Square, the robbery victim saw them as he walked out of Tesco. He had previously warned his friends not to approach them as they were armed with a knife. One of the girls in his group decided to approach the defendants and grabbed hold of the 15-year-old's coat. Speaking to another boy, he said: "Get your girl off me or I’ll hit her".

The boy and the girl attempted to take the defendants' balaclavas to expose their faces, and were successful in removing the 15-year-old's mask. The defendant and the boy began throwing punches at each other and a scuffle broke out. The boy became aware the 15-year-old was "swinging" towards his chest but described feeling "numb".

When both of the defendants ran off, the boy saw the 15-year-old holding a knife in his hand, which he later described as the biggest kitchen knife in a knife set with a blade between eight and 11 inches, with a dark coloured handle. He then realised he was bleeding and after checking under his top he saw a cut. His friends told him he had been stabbed and asked him to lie down.

Armed police arrived at the scene and the boy was taken to the University Hospital of Wales in Cardiff where he was treated for a 2cm wound to his left side, a 0.5cm wound to the top of his abdomen and superficial pin prick marks to his sternum and hip.

The 15-year-old was later arrested at his home address, and was found in possession of the vapes stolen from the two men. He later pleaded guilty to wounding with intent and two counts of robbery. The court heard he was of previous good character.

The 14-year-old was arrested outside his home address. He pleaded guilty to two counts of robbery, and the court heard he has eight previous convictions for offences including robbery, battery, possession of cannabis, burglary and fraud by false representation.

In a victim personal statement read to the court, the stabbing victim said: "I was stabbed by a male I did not know. The incident is still fresh in my mind and the realisation of its seriousness has not hit me yet. I have to be careful and slow when moving due to the injuries on my back which required stitches. The realisation I was stabbed hasn’t hit me yet. I honestly believe if the knife stabbed me in a vital area it would have been potentially serious or fatal. If the chest injury was a few inches away from where it was it could have gone into my ribs or heart. I am worried to go to the city centre now and will never go to Central Square again."

The first robbery victim said: "I was afraid I was going to get stabbed. I’ve seen them robbing people multiple times. They are dangerous people and could cause serious harm to people to get a small amount of money. They were aggressive. The fact they robbed me while carrying a knife in broad daylight makes me think they would have carried out their threats and stabbed someone. I believe if I didn’t hand over £25 it would have been me they’d have stabbed."

In mitigation, Adam Sharp, for the 15-year-old, said his client has spent time on remand in excess of six months. The barrister said the defendant had unstable and difficult upbringing, serious neglect, exposure to parental class A drug use, and social services involvement from a young age. Heath Edwards, for the 14-year-old, said his client is "easily led" and was not the "prime mover" or armed during the robberies.

Sentencing at Merthyr Tydfil Crown Court on Monday, the Recorder of Cardiff Judge Tracey Lloyd-Clarke said: "You are lucky the wounds were not more serious.... It's always a last resort for youths to be sent to custody. You are both still young but what you did was very serious."

The 15-year-old was sentenced to three years detention in a young offenders' institute. The 14-year-old was sentenced to three years and seven months detention in a young offenders' institute.

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