Dec. 22, 2016—Uber has removed its self-driving cars from California roads after state regulators moved to revoke their registration, according to a report by USA Today.

Hours after Uber launched the service in San Francisco, the DMV threatened legal action, arguing that the cars needed the same special permit as the 20 other companies testing self-driving technology in California, according to USA Today.

Uber argued that it does not need a permit because the cars cannot continuously drive themselves. The DMV said that the registrations that Uber received were improperly issued because the cars were not properly labeled as test vehicles, according to the report.