A teenager's Snapchat confession to a brutal attack on a school friend has seen him locked up for more than two years.

Luke Leggatt, 19, from Canterbury, used the social media platform to tell his victim's girlfriend: "I ****** your boyfriend up."

He sent the message after his own girlfriend, Niamh Gaffney, was arrested in connection with the unprovoked assault on Jay Baker at Kingsmead Field in Canterbury.

But it was Leggatt who had punched Mr Baker to the ground before stamping on his head and leaving him unconscious.

Miss Gaffney, who is no longer in a relationship with Leggatt, said she had been with the pair on August 20 when Mr Baker was attacked as he rolled a cigarette.

"We sat down and started having a couple of smokes, and Luke jumped Jay," she told Canterbury Crown Court.

"He punched him and he started stomping on him. I panicked and left.

"We had just all been talking. We were all sitting down and Luke stood up and literally punched him square in the face. He was proper stamping on his head."

Mr Baker lost consciousness during the assault, awaking with "a sore headache" to find his pouch of tobacco missing.

He said: "I sat there to roll a fag, put the fag in my lips, and that's all I remember."

Leggatt initially claimed he had acted in self-defence, alleging the first punch was thrown by Mr Baker.

But Judge Catherine Brown dismissed Leggatt's claim after witnesses denied this was the case.

Mr Baker's girlfriend arrived at the field after the attack, where she discovered her injured boyfriend.

Caroline Moonan, prosecuting, said: "She rushed over and found him bleeding and bruised, and she telephoned the police."

Mr Baker went to the Kent and Canterbury Hospital, before being sent to the QEQM in Margate for further tests.

Miss Gaffney was later arrested in connection with the attack.

But she was released after Leggatt sent the Snapchat message to Mr Baker's girlfriend on August 27, saying: "I ****** your boyfriend up, not Niamh - I suggest you ring the police and tell them that cos she's been arrested for this. I done it to Jay."

The young woman promptly screenshotted the message, and gave it to the police.

The court heard how Leggatt had previously confessed to a psychiatrist that he did not know why he carried out the attack.

But, speaking in court under oath, he claimed the psychiatrist was mistaken.

Leggatt pleaded guilty to robbery and unlawful wounding, but the hearing was held to establish the circumstances surrounding the incident.

Judge Brown found he had not acted in self-defence.

She said that while the severity of his attack warranted an immediate custodial sentence, she had to consider his lack of maturity.

'Your age may have been 18, but you function at a level that would be a year or so younger' - Judge Catherine Brown

Ms Brown said: "You are now aged almost 19. When you had just turned 18, you assaulted Jay Baker causing him grievous bodily harm, and you robbed him.

"This was a vicious and sustained attack.

"Quite why you suddenly lost your temper and attacked him is not clear.

"You may be almost 19, but I do not consider your adult age reflects your level of maturity.

"I consider it is appropriate that I sentence you on the basis that your age may have been 18, but you function at a level that would be a year or so younger than that."

Leggatt was sentenced to 27 months in a young offenders' institute.

"I hope that you do now realise that you need to take advantage of all opportunities that are open to you," added Ms Brown.

"Only you can decide to change.

"Life is going to be very unpleasant to you in all sorts of ways. And that's not to your benefit, or society's benefit.

"You are now an adult, and need to start to act like an adult."

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