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Elon Musk did not defame a British cave explorer when he called him “pedo guy” in an angry tweet, a Los Angeles jury has found.

Vernon Unsworth, who participated in the rescue of 12 boys and their soccer coach trapped for weeks in a Thailand cave last year, had angered the Tesla CEO by belittling his effort to help with the rescue as a “PR stunt.”

During the court hearing, Unsworth who helped rescue 12 young boys and their soccer coach from a flooded cave in Thailand says he felt “dirtied” after being “branded a paedophile” by Musk.

Musk said Unsworth’s comments in an interview with CNN were an unprovoked attack on his sincere and voluntary efforts to help in the rescue by putting a team of engineers on the job around the clock to design the mini-pod.

He lashed out with a phrase that he insisted only meant “creepy old man” and wasn’t literally calling Unsworth a pedophile.

Unsworth’s attorney had earlier suggested to a federal jury on Friday (local time) that it award $US190 million ($A277.66 million) to his client.

Attorney Lin Wood said the suggested award would include $150 million as a “hard slap on the wrist” to punish Tesla CEO for what he said was akin to dropping an atomic weapon on his client.

“What in the world would it take to discourage Elon Musk from ever planting a nuclear bomb in the life of another person?” Wood said.

Musk, who said his stock in Tesla and SpaceX is worth about $20 billion, insisted in his testimony that the phrase he tweeted off-the-cuff “was obviously a flippant insult, and no one interpreted it to mean pedophile.”

Musk’s lawyer told the jury the tweet did not rise to the level of defamation. Attorney Alex Spiro said Unsworth also failed to show actual damages. A jury of five women and three men deliberated for less than an hour in the afternoon in U.S. District Court.

Unsworth had ridiculed Musk’s effort to help in the rescue by having engineers at his companies, including Space X and The Boring Co., develop a mini-submarine to transport the boys.

Despite working around the clock to build the sub, Musk arrived in Thailand late in the rescue effort and the craft was never used. Unsworth called it nothing more than a “PR stunt” and said Musk could stick the sub “where it hurts.”

Our Aussie cave rescue heroes honoured Nine Australians have been honoured for their efforts during the Thai cave rescue that freed 12 boys and their soccer coach this month.

In his closing argument, Wood called Musk a “billionaire bully” who lied when he claimed “pedo guy” only means “creepy old man” and said his apologies to Unsworth were insincere.

“When Elon Musk tweets something it goes around the world,” Wood said.

“It can never be deleted.” Unsworth testified that he had to sue Musk for defamation because if he didn’t, the allegation would seem true.

Spiro mocked Unsworth’s claims that he had been shamed and humiliated and that the tweet effectively sentenced him to a life sentence without parole.

Spiro noted that Unsworth had been honored by the queen of England and the king of Thailand, had his photo taken next to British Prime Minister Theresa May and been asked to speak at schools and contribute to a children’s book, which showed that no one took Musk’s insult seriously.

“People accused of pedophilia don’t get celebrated by world leaders,” Spiro said.

“Kings and queens and prime ministers don’t stand next to pedophiles.”