Xiaomi announced on Tuesday it was collaborating with Chinese police following a fatal accident on March 29 involving a SU7 electric vehicle and that it had provided system and driving data to assist in the investigation.
The incident marks the first major accident involving the SU7 sedan, which Xiaomi launched in March last year and since December has outsold Tesla's Model 3 on a monthly basis.
Xiaomi's shares, which had risen by 34.8% year to date, closed down 5.5% on Tuesday, underperforming a 0.2% gain in the Hang Seng Tech index.
Xiaomi did not disclose the number of casualties but said initial information showed the car was in the Navigate on Autopilot intelligent-assisted driving mode before the accident and was moving at 116 kph (72 mph).
A driver inside the car took over and tried to slow it down but then collided with a cement pole at a speed of 97 kph, Xiaomi said.
The accident in Tongling in the eastern Chinese province of Anhui killed the driver and two passengers, Chinese financial publication Caixin reported on Tuesday, citing friends of the victims.
In a rundown of the data submitted to local police posted on a Weibo account of the company, Xiaomi said NOA issued a risk warning of obstacles ahead and its subsequent immediate takeover only happened seconds before the collision.
Local media reported that the car caught fire after the collision. Xiaomi did not mention the fire in the statement.
Xiaomi began manufacturing EVs last year with the launch of the SU7 sedan after selling smartphones, household appliances and smart gadgets for most of its 15-year history.
The company has two versions of smart driving systems on its SU7 EVs. The higher-end LiDAR-mounted version, as opposed to the pure vision version, enables urban navigation features such as collision avoidance and special vehicle recognition.
Xiaomi said the car involved in the accident was a so-called standard version of the SU7, which has the less-advanced smart driving technology without LiDAR.
