By Jiahui Huang

Xiaomi's shares fell in Hong Kong after a fatal car accident involving one of its electric vehicles in China, which could raise concerns about the safety of its advanced driver-assistance system.

Shares of the company, known for its consumer electronics but now increasingly also for smart cars, fell 5.5% to 46.50 Hong Kong dollars, equivalent to US$5.98, on Tuesday afternoon, making it the top decliner on Hong Kong's benchmark Hang Seng Index.

The sudden drop came after the company said that one of its SU7 models was involved in a lethal accident on an expressway in China's Anhui province. Three people died in the accident, according to Chinese media reports.

Like many other Chinese EV makers, Xiaomi has been marketing its advanced driver-assistance features heavily as the industry ramps up development of autonomous-driving technology.

In a post on social-media site Weibo, Xiaomi said the SU7 model had been in "navigation on autopilot" assisted-driving mode, traveling at an average speed of 116 kilometers per hour, when the accident occurred on the night of March 29.

Xiaomi gave a timeline of the accident in its Weibo post. According to the post, a systems log showed that the car's driving system sent a notification after detecting obstacles on the road and started to lower its speed. The driver then took over the vehicle, which switched to human-driving mode, the company said. Seconds after the driver took control, the crash happened, and the last available speed was at about 97 kilometers per hour, it said.

Xiaomi's post didn't mention the three deaths. The company said it has dedicated a special team to support a police investigation into the accident.

The fatal incident has attracted public attention, becoming a trending topic on Chinese social media. Users on social-media sites expressed concern about the safety of advanced driving-assistance systems, which are widely used in EVs in China and have became one of the selling points for many brands.

The SU7 model, Xiaomi's first-ever car, has had a successful launch in China's overcrowded, competitive EV space, notching robust sales since it came onto the market last year. The company's fast-growing EV division reported gross profit margin of 18.5% in 2024--its first full year of results--making it one of the few Chinese EV makers with a double-digit gross profit margin.

Shares in Xiaomi are up 35% year to date.

Write to Jiahui Huang at jiahui.huang@wsj.com

(END) Dow Jones Newswires

April 01, 2025 05:17 ET (09:17 GMT)

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