BEIJING — Tesla‘s sales in China more than doubled last year amid the coronavirus pandemic, according to a filing out Monday.

The electric car maker’s sales in China of $6.66 billion last year accounted for about a fifth, or 21% of the $31.54 billion total.

In 2019, Tesla’s China sales reached $2.98 billion, just 12% of the $24.58 billion total.

The U.S. remained Tesla’s largest market, with sales rising 20% last year to $15.21 billion and accounting for roughly half of total sales.

Tesla began ramping up production last year at its factory in Shanghai and selling China-made cars to the local market.

The company’s Model 3 was the best-selling electric car in the country in 2020, according to China’s Passenger Car Association. The automaker also began deliveries of a new model, a China-made Model Y, to local customers this year.

However, Tesla faces competition in the local market from Chinese electric car start-ups like Nio and Xpeng, while regulatory scrutiny has increased.

On Monday, China’s State Administration for Market Regulation said on its website that it and four other government departments recently met with Tesla’s local subsidiaries over an increase in consumer reports of vehicle problems.

Among several incidents that garnered attention on Chinese social media in the last few weeks, a Model 3 reportedly exploded in a Shanghai parking garage in January. Last week, Chinese authorities said Tesla needed to recall more than 36,000 cars due to a touchscreen failure.