On Tuesday, Uber casually announced that the company has been hauling freight with autonomous trucks on Arizona highways for some time now.

Though Uber made the announcement that they are moving freight for real live clients along Arizona highways, they’ve kept mum on the details. They will not disclose what the trucks are hauling or what companies they’re working for. Uber has also refused to say how many autonomous trucks they’ve deployed or the number of loads that they have delivered.

Uber says that they are now moving freight along highways between a number of transport stations. When an autonomous semi truck enters a station near an urban area, a human driver will take over the rest of the short route and deliver the freight. Uber’s goal is to take this transfer hub model and use it around the country.

The trucks are only operating on highways at the moment, and aren’t yet capable of navigating city streets, Uber’s self-driving truck product lead, Alden Woodrow, said.

Currently while the program continues to develop, regulations stipulate that a driver must be in the seat of the self-driving vehicle.

Could Automated Tech Keep Drivers Closer To Home?

Woodrow said trucking with its long hours and time away from home isn’t an especially popular job, but he thinks short-haul trips is one way to provide drivers with a more palatable alternative.

“The bigger question for us is how do we make sure we get a younger generation interested in this?” he said.

While its autonomous vehicle program has gotten Uber into trouble more than once, like when it rolled out self-driving cars to passengers in San Francisco without a license and when it was sued by Google for allegedly stealing self-driving car technology — the company is now looking to work with regulators and do things by the books.

Uber is mostly known for its ride-hailing service, which matches passengers with drivers through a smartphone app. But over the last three years, it has ventured into driver-less vehicles. Uber is now testing cars and trucks in Pennsylvania, California and Arizona.