Vernon Unsworth, a British cave diver who helped rescue 12 Thai children trapped in a cave in July, is suing Tesla (TSLA) CEO Elon Musk for libel and slander, according to a lawsuit filed in a U.S. district court in California.

“Elon Musk falsely accused Vern Unsworth of being guilty of heinous crimes,” Unsworth’s attorney, L. Lin Wood, said in a statement. “Musk’s influence and wealth cannot convert his lies into truth or protect him from accountability for his wrongdoing in a court of law.” Wood added that a separate lawsuit is being filed in London.

The situation began in July after Musk offered a submarine to rescue a Thai soccer team trapped in a cave. Unsworth referred to it as “nothing more than a PR stunt.” In response, Musk called Unsworth “pedo man” on Twitter. After speculation that Unsworth could sue Musk, the billionaire entrepreneur deleted the tweet and apologized.

‘I f***ing hope he sues me’

Unsworth’s lawyer had indicated to Musk that a lawsuit was being prepared.

“I am in the process of preparing a civil complaint for libel against you,” Wood, an Atlanta-based defamation lawyer, wrote to Musk (who is also the CEO of SpaceX and Neuralink) on August 6. “In an attempt to avoid litigation and to see the public record corrected, I invite you or your legal representatives to contact me.”

Musk sent another series of inflammatory tweets at the end of August, saying it was “strange” that Unsworth had not sued him after being referred to as a pedophile, implying that his silence made the accusations valid.

In part titled “Musk’s False and Defamatory Accusations,” the lawsuit cites Musk stating that “I fucking hope he sues me.”

Libel is a type of defamation that consists of a published statement. While Unsworth didn’t specify whether he wanted to sue in the U.S. or U.K., he could have a case in either country, according to two lawyers who specialize in defamation.

American lawyer Kenton Hutcherson previously told Yahoo Finance that Unsworth would have a case in the U.S., under any state’s law, if he chose to pursue a lawsuit. In order to win a libel lawsuit in the U.S., one must show that the defendant published a false statement either negligently or with actual malice.

Hutcherson noted that Elon Musk’s tremendous amount of social influence — including 22.4 million Twitter followers and multiple companies that benefit from free publicity — would work against him.

“The court is going to assume that it is going to cause the plaintiff personal injury,” he said. “It suggests sexual impropriety.”

Unsworth will also have a strong case in the U.K., which has notoriously strict laws related to libel. In the U.S., a person suing for libel bears the burden of proof. But in the U.K., a defendant has to prove their statement is not libelous.

“Referring to an individual as a ‘pedo’ is an extremely serious allegation which is highly defamatory and would almost certainly cross the threshold in terms of causing serious harm to one’s reputation, a prerequisite for bringing a libel action in English law,” British lawyer Megan O’Boyle told Yahoo Finance.

Hence, in the Musk situation, “if the diver’s reputation has been seriously harmed here in England, he can sue,” said O’Boyle.

‘I lose confidence in this guy by the day’

These legal issues are the latest troubles that the tech pioneer has gotten himself entangled in recently. Earlier in the month, Musk found himself in hot water with investors after tweeting that he was seriously considering taking Tesla private and asserting that he had secured funding as well as investor backing. Neither assertion was ever substantiated.

“I lose confidence in this guy by the day,” Yahoo Finance’s Rick Newman said on Midday Movers said in August. “I’m starting to wonder if he’s qualified to run a public company. The board of Tesla needs to sit this guy down … He’s inviting lawsuits and it’s not even the first one in the last month.”

An increasing number of others, including hedge fund CEO Ross Gerber, agree that Musk needs to — at the very least — tone down his tweeting.

Aarthi Swaminathan contributed to this report.

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