A teenager has been sentenced to a year in prison for assaulting a boy in Verulamium Park in St Albans, in a fight which resulted in another teenager being stabbed.

The defendant, who was 15 at the time, was part of a group of boys who attacked a 16-year-old in the park on June 15, as they celebrated the end of their GCSE exams. The victim was punched and kicked until he lost consciousness. When the victim’s cousin, also 16, stepped in to defend him, one of the boys stabbed him in the stomach with a 10-inch knife.

The defendant, who is now 16, appeared in court on Wednesday, December 19 charged with assault for his role in beating the first victim unconscious.

Abbe Arnold, defending, said: “He was taken away from his family for six months and placed in a foster home a considerable distance away. I would submit that for a young man who is quite vulnerable that was a significant punishment in itself.

“The foster home was horrendous. There were several children running around and there were dogs everywhere. He had nothing to do.”

The defendant submitted a letter to the judge expressing his own perspective on the assault, stating that he was sorry for his actions and had learnt a lot from this.

Ms Arnold said: “It’s a heartfelt letter. It’s a true reflection of how he feels. He clearly has challenges as far as his literacy goes and he finds it extremely hard to express himself. He still has a lot of growing up to do and he hasn’t had the best start in life.

“He is a young man and still has his future ahead of him and this really is the turning point for him. Since this offence he has not committed any further offences. He has been seeking work and he has been making positive changes in his life.”

The defendant was previously convicted for battery and actual bodily harm, which occurred in 2016, and for burglary, which took place in 2017.

Judge Michael Kay QC said: “A large number of students were gathered in Verulamium Park following the end of their GCSE exams. It should have been a time of celebration.

“There were anywhere between 60 and 100 teenagers gathered there. It was peaceful until a group of youths approached a young man because of some trivial dispute between him and [a relative of the defendant].

“It does not matter a jot what is behind all of this. The group approached the victim who was sitting with a number of other young people in a circle in the park. One of the group asked him to come over to some other area so they could have a chat with him. It was clearly a menacing approach.”

The group punched and kicked the boy in the head until his cousin intervened and was stabbed. The stabbing victim had to be airlifted to hospital for emergency surgery to repair his gallbladder and stomach, and also suffered a laceration to his scalp which required treatment.

Judge Kay, speaking about the boy who was knocked unconscious, said: “This was a cowardly, aggressive violent attack in full view of very many other young people.

“This was a joint attack by a number of people involved in the punching and kicking. The victim has continued to suffer from the mental effects of being assaulted in such a violent way. He also feels guilty because his cousin was stabbed when that was probably intended for him.

“You worked in numbers because that’s how cowards work.”

The judge told the court that the defendant was assessed to be at ‘high risk’ of re-offending and expressed doubt that the letter he wrote was genuinely remorseful.

The offender was sentenced to 12 months in prison, and must serve at least six months before being considered for release. Judge Kay said: “The message of all of this is if you behave in this manner you will receive a custodial sentence.”

The teenager who stabbed the other victim is due to be sentenced on January 25.

St Albans chief inspector Lynda Coates said: “The stabbing victim was lucky to survive this horrendous and violent attack and no doubt the traumatic events of that day will stay with both of the young victims and their families for the rest of their lives.

“The domino effect of violent crime is far reaching and these serious convictions will stay with the teenage offenders for the rest of their lives. Their own families will have also suffered the heartache of seeing their loved ones go through the criminal justice system, stand trial and be sentenced.”