China’s market regulator said Tesla Inc. will fix software in more than 1 million vehicles to reduce the chance of accidents, the regulator said on Friday.

The action is described as a product recall under Chinese regulations, the regulator said, but it was not immediately clear if drivers might need, or would be eligible, to return vehicles to Tesla for refunds.

From May 29, the U.S. automaker will issue over-the-air software updates to 1.1 million units of its Model S, Model X, Model 3 and Model Y cars, both imported and China-made, the State Administration for Market Regulation said in a statement.

The regulator said the vehicles concerned did not allow drivers to turn off regenerative braking or provide enough warnings when drivers stepped on the accelerator pedal hard, which, combined, could increase the risk of collision.

The update will restore the option of switching off regenerative braking and warn drivers when they step hard on the accelerator pedal, it added.

Tesla was not immediately available for comment.

Regenerative braking works to save energy from the process of slowing a car, feeding the surplus to batteries to increase its driving range. Tesla had disabled the option to switch off the technique on cars produced after 2020.

Some consumers in China welcomed the technology, also known as one-pedal driving, as it enabled them to bring a vehicle to a complete halt without use of the brake pedal.

However, others complained it could confuse drivers and increase the risks of misstepping on accelerators.

Chinese police have been investigating a crash involving a Model Y car in which a motorcyclist and a high school girl died and three people were injured when the driver lost control of the vehicle last November.

At the time, Tesla said videos showed the car’s brake lights were not on while it was speeding and data showed issues such as there being no action to step on the brakes throughout its journey.

Reporting by Reuters’ Beijing Newsroom; Editing by Jacqueline Wong