Zoox autonomous cars are hitting the streets of San Francisco with no steering wheel, driver's seat, or pedals.

Although the Amazon-backed company has been operating in the city since 2017, a human driver has been in the vehicle, ready to intervene if necessary.

Zoox has now "passed all critical safety measures," and the vehicles are free to operate themselves. They qualify as Level 3 on the autonomy scale, a step above the Level 2 Waymo cars that are also on the road in San Francisco as a paid rideshare service.

For now, only Zoox employees will be taking autonomous rides. The launch will start in the SoMa neighborhood and expand to more areas of the city if all goes well.

Zoox makes traditional-looking vehicles with a steering wheel, largely for testing purposes, but its claim to fame is a boxy car that hit the road last year. These are the only vehicles operating on public roads "without traditional manual controls," says Jesse Levinson, Zoox co-founder and CTO. The company fleet also includes traditional-looking SUVs with a driver's seat, steering wheel, and pedals, presumably for testing with a safety driver.

Zoox is already testing on the streets of Las Vegas, particularly around The Strip. Last week, it expanded the area in which its vehicles operate in the city, or the "geofence," to gather more data to train its AI models. It plans to open up rides there to public passengers in 2025.

"The data we gather in Las Vegas will be crucial for improving our service even further," Zoox says. "What Zoox learns in Vegas won't stay in Vegas."

The National Highway Traffic Safety Administration (NHTSA) is currently investigating two minor crashes involving Zoox vehicles that stopped abruptly. Another NHTSA probe into Tesla's Level 2 self-driving autonomous system is also ongoing. Tesla hopes to begin operating its robotaxi service in California and Texas next year, though it has not yet gained regulatory approval.