Tesla shares have sunk after US regulators took legal action against co-founder Elon Musk for alleged securities fraud.
On Thursday the Securities and Exchange Commission filed a lawsuit over claims made last month by Mr Musk that he had funding to take the company private.
The billionaire boss of the electric carmaker called the action unjustified.
But the filing was a potentially serious blow for the company, which was already under financial strain.
Mr Musk has led the electric carmaker as chief executive since 2008, presiding over its rise into a company with a market value that rivals Ford and General Motors.
His celebrity status and reputation for entrepreneurial vision attracted investors and legions of fans – even though the firm has consistently lost money and struggled to hit manufacturing targets.
Tesla’s shares closed 13.9% lower. During the trading session on Friday, shares fell by 15%.
