General Motors and its autonomous technology company Cruise Automation are testing self-driving cars on the streets of Scottsdale, Arizona.

Testing of self-driving electric Chevrolet Bolts began in Arizona about two weeks ago. It's the second city for GM's real-world tests. Autonomous Bolts with Cruise Automation software have been driving around San Francisco since May 20.

GM spokesman Kevin Kelly says the company is considering other cities for tests but wasn't ready to announce locations.

He would not say how many Bolts are being tested. Although the cars drive autonomously, Kelly says they all have human backup drivers.

GM acquired San Francisco-based Cruise Automation in March for $581 million in cash and GM stock. Kelly says the company has opened an office in Scottsdale.