Twelve boys and their football coach were rescued from the Tham Luang cave complex by an international team and after a week of intense drama.

The chief executive of the tech giant Tesla offered to assist the rescue mission by providing a submarine. The request was turned down. Musk lashed out on Sunday, saying he would make a video proving that his “mini-sub” would have been successful and adding: “Sorry pedo guy, you really did ask for it.”

The accusation, presented without evidence or context, was directed at Vern Unsworth, a British cave explorer who recently said Musk’s attempt to help the rescue effort was a “PR stunt”. No evidence has emerged to substantiate Musk’s claim of pedophilia.

“It just had absolutely no chance of working,” Unsworth said in a widely shared interview. “He had no conception of what the cave passage was like. The submarine, I believe, was about 5ft 6in long, rigid, so it wouldn’t have gone round corners or round any obstacles.”