BEIJING — One of Pony.ai‘s robotaxis caught fire for the first time on Tuesday, with no people harmed in the incident, the U.S.-listed Chinese startup told CNBC.

The company did not disclose the reason behind the fire. Videos purporting to show the incident in Beijing had circulated on social media. CNBC could not independently verify this footage.

Electric cars such as those from Tesla, which is trying to develop its own robotaxi, have previously caught blaze.

Pony.ai said that one of its fully self-driving vehicles was detected as having an abnormal status in Beijing around 9:30 a.m. local time on May 13.

The company operates its cars using software that can be centrally monitored.

There were no passengers on board at the time of the incident, and the vehicle automatically initiated an emergency stop, resulting in no collisions or injuries, Pony.ai said. It noted that service workers arrived within two minutes of receiving the alert.

“During the handling process, the vehicle caught fire,” Pony.ai said. “The on-site staff coordinated with relevant authorities to execute containment measures, safely and effectively resolved the incident. The specific cause is currently under investigation.”

Shares of Pony.ai fell more than 10% overnight. The stock is up more than 25% for the year so far.

The company operates robotaxis in parts of the major Chinese cities of Beijing, Shanghai and Guangzhou, for a total of more than 250 cars across the country as of late November.

Pony.ai in late April announced it was working with Toyota, Beijing’s BAIC and GAC’s Aion for new robotaxi vehicles that the company claimed can cut costs by 70%. 

Chinese autos companies have increasingly ramped up competition with U.S. rivals, with China-made electric cars rapidly becoming dominant players in the domestic market at the expense of Tesla and traditional foreign automakers.