A thug who strangled a Pokemon Go enthusiast in a shopping centre car park before stamping on his head and leaving him to die has been jailed for life.

John Dickson will have to serve an 18-year sentence before he will be considered for parole.

Maidstone Crown Court heard Dickson, 27, put Carl Gregory in a choke hold until he lost consciousness and collapsed.

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His co-accused, Christopher Pollard, was acquitted of murder and an alternative charge of manslaughter yesterday.

He wiped away tears of relief after the verdicts were returned. He was taken to the cells to be released.

VIDEO: John Dickson will face a minimum of 18 years behind bars

Judge Adele Williams told Dickson: “You are cold and calculating, showing no emotion whatsoever. In my judgement you are a very dangerous individual.

“On all the evidence before me I am sure there came a time during the incident when you formed the intention to kill Carl Gregory.

“You went on applying the choke hold after he had become unconscious. You literally held his life in your arms and you showed him no mercy.

The judge stressed: “The sentence of this court is life imprisonment. That means you will not be released unless the parole board considers it is save to release you.

“You may serve the minimum term. You may serve more than the minimum term. You may never be released.”

The pair had gone to The Link Retail Park near Westwood Cross in Broadstairs to confront Mr Gregory after he insulted his ex-girlfriend - Pollard’s friend - on a social networking site.

He had posted an offensive picture relating to Chloe Lemare on Facebook and called her a slag, the jury of eight women and four men heard.

A row erupted after Pollard arranged to meet Carl Gregory in a car park outside Hobbycraft on the evening of October 4 last year.

Pollard, 20, took his friend Dickson with him and they ended up making a joint attack on Mr Gregory, it was alleged.

Prosecutor Philippa McAtasney QC said Pollard kicked the victim with steel cap boots and Dickson held him in a choke hold, which led to his death.

Dickson, of Northdown Road, Cliftonville, and Pollard, of Brimstone Hill, Meopham, denied the charges.

The court heard Dickson had previously been sentenced to six years detention for causing grievous bodily harm with intent after he shot a stranger with a BB gun, leaving a pellet embedded in his face.

He showed no emotion as Judge Williams told him: “You have been convicted of the brutal murder of Carl Gregory on the clearest and most compelling evidence.

“This was a truly senseless killing. It all began with a futile argument on social media when Christopher Pollard took offence on Chloe Lemare’s behalf and at her behest.

“Christopher Pollard then sent deeply unpleasant and threatening messages via Facebook and text messages to Carl Gregory.

“They included threats to Carl Gregory’s family. Carl Gregory was goaded into meeting him at Westwood Cross, goaded into going there alone.

“I am sure you were aware of those text messages. You were taken along by Christopher Pollard because you were older, stronger and more experienced.

“This case well illustrates some of the dangers of young people on social media. It shows how an argument can escalate and be blown out of all proportion because of the speed of the communications.”

The judge said Pollard was the first to use violence. There was a fist fight and it became two on one when Dickson intervened.

"You are cold and calculating, showing no emotion whatsoever. In my judgement you are a very dangerous individual" - Judge Adele Williams

“It became a more vicious fight,” she said. “You then made the decision to place a choke hold around Carl Gregory’s neck. You compressed his neck for approximately two minutes - one minute and 57 seconds.

“You knew exactly what you were doing and how dangerous it was. You admitted as much in interview and evidence. That compression of his neck killed him.

“You then got up and forcefully and gratuitously stamped on his head as you were leaving in an attitude of the utmost contempt of him.

“That last act was clearly captured on CCTV footage. You and Christopher Pollard callously left Carl Gregory at the scene. You offered him no assistance and called no assistance for him.”

Judge Williams said Mr Gregory was vulnerable as he suffered from Asperger’s Syndrome and ADHD.

“He had his whole life ahead of him,” she continued. “He was loyal and faithful. He liked gaming, modern technology and Pokemon Go.

“I have read a victim personal statement from his mother. It makes very moving reading indeed. She describes the devastating loss she and all his family feel.

“She describes the pain they have already suffered and are suffering and will continue to suffer in the future. Their grief and anguish is still raw and immeasurable.

“They are haunted by the fact his death was so very unnecessary and that they were not there during his last moments.

“Nothing I can say, nor can it in any way diminish, their loss and grief. It couldn’t possibly do so.”

The judge told Dickson: “You have shown not a flicker of remorse or regret.”

Dickson’s QC Oliver Saxby said the victim’s vulnerability had to be put into context.

Dickson, he said, had never met Mr Gregory and did not know him. Dickson, therefore, was “not the least bit aware” of the extent of his vulnerability.

"He had his whole life ahead of him. He was loyal and faithful. He liked gaming, modern technology and Pokemon Go" - Judge Adele Williams, on Carl Gregory

“Vulnerability played only a minimum part in what happened on the evening in question,” he said.

It was not accepted there was a lack of remorse by Dickson.

Mr Saxby said an expert could only “opine or speculate” on how long Dickson held Mr Gregory in the choke hold, but the evidence was clear he held on for too long.

“This was not John Dickson’s problem in the first place,” he continued. “He only became involved midway through the incident.

“The intention was initially to intervene and separate. His involvement was, therefore, in the heat of the moment. There was an element of self-defence in how he reacted.”

Miss McAtasney had previously told the jury of eight women and four men: “The prosecution case is that both these defendants murdered Carl Gregory.

“It is the prosecution case that in the course of the attack Carl Gregory was placed in a choke hold and asphyxiated for such a period of time that he became unconscious and sadly died.

“Since their arrest and detention both defendants have sought to absolve themselves of responsibility or shift the blame to the other for Carl Gregory’s death.”

“The prosecution say both these defendants committed the crime together.”

Mr Gregory, 20 and from Ramsgate, had been diagnosed with ADHD at a young age. He was said to enjoy computer games, music and football.

He met Miss Lemare about 18 months before his death. The relationship ended in August last year but they remained in contact and played Pokemon Go together.

Pollard lived with his girlfriend and a month before the alleged attack Dickson moved in with them. Dickson was head gardener at Tudor House museum in the town and Pollard also worked there.

After the verdicts, Detective Sergeant Ross Gurden of the Kent and Essex Serious Crime Directorate said: “This was a tragic death of a popular young man who had his whole life in front of him.

“Carl Gregory is sorely missed by his family and friends due to the actions of John Dickson, who went out of his way to confront him. I hope today’s outcome is of comfort to all those who loved Carl.

“I hope this case reinforces the message that the use of violence to resolve issues can result in life changing consequences. Dickson is a young man who will now serve a considerable length of time behind bars as a result of a complete disregard of the consequences of his actions.”