At a critical time for electric vehicle maker Tesla Inc. (TSLA), as it tries to prove that it can sustain production levels for its first mass market vehicle, its outspoken CEO and founder Elon Musk continues to burn bridges with public regulators, analysts, journalists, former employees and now a British diver involved in the recent celebrated rescue of a Thai soccer team. (See also: Tesla Used Red Bull to Hit Model 3 Goals: Bloomberg.)

Tesla stock plunged 3% on Monday after Musk lashed out at British diver Vernon Unsworth, tweeting “sorry pedo guy, you really did ask for it.” Unsworth has earlier criticized the tech billionaire’s plan to use a miniature submarine to assist in the recent rescue efforts in Thailand. The diver has told reporters that he is considering suing Musk.  Musk's allegations about the diver have since been deleted from his Twitter Inc. (TWTR) page, which has 22 million followers.

Musk's tweets and reports of his contributions to Republican political groups have rattled investors, sending the stock down more than 16% since last month, at a time when bears are increasingly skeptical that the firm can continue to sustain operations without raising more cash. 

Investors Urge Musk to Focus on Core Tasks

“This thing is unraveling,” said Gordon Johnson, the managing director of Vertical Group, a New York-based investment research group, as reported by the Washington Post. “You had a very big shareholder last week say they want him to focus on executing and stop with the tweets—and then, this weekend, you get more tweets. What’s his angle? What is he doing? … He keeps promising all of these things, and he keeps missing, and he’s not being held to task.”

Jamie Anderson, a partner at Scottish asset management firm Baillie Gifford, one of Tesla's three largest shareholders, told Bloomberg last week that Musk needs space to work through issues and focus on resolving the automaker's "execution issues." "It would be good to just concentrate on the core task" of making cars, said Anderson. 

Loup Ventures analyst Gene Munster, a Tesla bull, said the comments have raised concerns regarding the CEO's durability and "maturity," reported The Washington Post. "They have such a great story to tell, and it's getting lost in the noise."

In an interview last week, Musk told Bloomberg that he was trying to be nicer on Twitter, acknowledging that it is not a no-holds-barred battleground where, "if you attack me, it is therefore OK for me to attack back." (See also: Tesla Will Turn a Profit by Sept.: Gene Munster.)