Shares in electric vehicle maker Tesla plunged on Monday as investors in the company were not too impressed after CEO Elon Musk called a British caver involved in the rescue of 12 Thai children last week a "pedo".
In response, Musk wrote another post on Twitter on Sunday, promising to release footage of his submarine in action.
He said that the child-sized submarine Musk provided during the rescue operation "had absolutely no chance of working".
"The caver told AFP he would make a decision when he flies back to the United Kingdom this week, but said the episode with Musk 'ain't finished, '" the news agency reported.
"I do not actually see the checks (changed that policy today)", Musk said in one.
In his defence, Musk posted on Twitter that leaders of the Thai rescue, in which all the boys and their coach were safely extracted, had asked him to build the mini-sub.
Mr Unsworth yesterday said he had only heard about the tweets.
"I believe he's called me a pedophile", Unsworth responded in an interview with the Guardian newspaper.
Munster and other investors said that while they've sometimes agreed with Musk's Twitter statements in the past, they couldn't back him up this time. Tesla slid 2.8% during official market hours Monday, before declining more than 1% in after-hours trading.
"It's totally gratuitous. It wasn't necessary", Mr Kay said of the Musk insult to the Briton, who has threatened a lawsuit.
Analysts said Musk's "pedo guy" comments had ensured the flap over the submarine would again steal Tesla's thunder at a critical time, when Musk should be focused on promoting the company's progress in manufacturing the Model 3.
Unsworth's wife said Monday that her husband was returning to Britain on July 19, where he will speak to lawyers, Reuters reports.
Mr Musk "is under a lot of pressure and we're seeing pressure fractures", Mr Kay said. "I should probably say nothing more often".
Anderson and others noted how Tesla has been at the forefront of electric vehicle development and reducing carbon emissions - and Musk's controversial Twitter comments could jeopardize that.
But while Musk also defended his donation by mentioning that he has donated almost $6 million to the Sierra Club, an environmentalist group fighting climate change, he is also helping keep fringe extremists in the Republican Party in power.