Tesla may be the hottest car company in the United States, but the electric automaker isn't faring too well in the world's biggest auto market. 

June Jin, vice president of communications at Tesla's China operations, has left the company after less than a year, Bloomberg reported. Tesla has nine stores and service centers in six Chinese cities as well as 700 charging stations in 70 cities throughout the country, according to Bloomberg.

Palo Alto, Calif.-based Tesla sold just 120 of its luxury electric sedans in China last month, coming in well below its ambitious sales targets, Reuters reported in an exclusive.

Tesla shares dropped 7 percent last month based on fourth-quarter China sales that CEO Elon Musk described as "unexpectedly weak," adding that "We'll fix the China issue and be in pretty good shape probably in the middle of the year."

Musk, who has a reputation for being both meticulous and hot-tempered, has threatened to fire executives over weak China sales.

In an internal email from late January, Tesla's leader said he would fire or demote managers in China if sales are "not on a clear path to positive long-term cash flow," sources who had seen the email told Reuters. 

Musk said that company managers who can't bring up sales "will be asked to leave or assume a more junior role. This has already happened in China and will likely happen in some other countries, too."

One of Reuters' sources provided a transcript of the email.

Musk has aggressive production targets for Tesla, aiming to reach 500,000 units by 2020, compared with 50,000 cars projected for this year.

China executives have been bailing on Tesla, with manager Veronica Wu leaving in mid-December not too long after her predecessor, Kingston Chang, departed the company last March.

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