SpaceX and Tesla Chief Executive Officer Elon Musk renewed his attack on British cave diver Vernon Unsworth, who was instrumental in saving the lives of 12 schoolboys and their football coach marooned in a cave in Thailand for over 10 days in July.

In an email to Buzzfeed last week, Musk called the diver a “child rapist” who had moved to Thailand to marry a child. In July, Musk had apologised to Unsworth after calling him “a pedo” on Twitter. Unsworth had then said he was considering legal action against Musk.

In a fresh attack, Musk called Unsworth a “child rapist” but did not provide any evidence to support his allegation. “I suggest that you call people you know in Thailand, find out what’s actually going on and stop defending child rapists,” Musk wrote in one email. “He’s an old, single white guy from England who’s been traveling to or living in Thailand for 30 to 40 years, mostly Pattaya Beach, until moving to Chiang Rai for a child bride who was about 12 years old at the time.”

In another email, he alleged that Unsworth had falsely claimed that Musk was asked to leave by the Thai government. “Thai Prime Minister thanked me personally per attached docs [documents],” wrote Musk. “I went all the way to area 3 with the Thai SEAL team, who were awesome.”

Unsworth denied the accusations through his lawyer L Lin Wood on Wednesday, calling them “vindictive and vicious lies”. “After deleting the initial accusation and tweeting an apology, Mr Musk has continued to republish his false and unsupportable accusation,” Wood said in a statement. “His conduct demonstrates that his recklessness is intentional and designed to harm Mr Unsworth.”