Uber is shutting down its self-driving truck program, the company acknowledged on Monday. It's the latest example of Uber scaling back its self-driving technology efforts in the wake of a deadly Uber self-driving car crash in March.

Uber's self-driving truck program has been embroiled in controversy since Uber acquired the unit two years ago. The acquisition price was reportedly $680 million, though the actual cost may have been much less than that. Previously, it had been a startup called Otto, led by controversial ex-Waymo engineer Anthony Levandowski. Waymo sued Uber, arguing that Levandowski had taken Waymo trade secrets with him on the way out the door.

Uber wound up firing Levandowski in 2017 and settling the lawsuit with Waymo earlier this year, clearing the way for Uber to focus on developing the self-driving truck technology. In March, Uber began testing its self-driving trucks hauling real freight. The company developed an innovative hybrid model for self-driving truck deliveries, where a human driver would handle tricky urban driving at the beginning and end of the trip, while software could handle the relatively simple long-haul highway driving in between.

But days later, an Uber self-driving car struck and killed pedestrian Elaine Herzberg in Tempe, Arizona. Uber put its self-driving testing program on hold shortly afterward and laid off most of its safety drivers. Only last week did Uber take its first tentative step toward resuming tests, using self-driving cars in the Pittsburgh area.

"We’ve decided to stop development on our self-driving truck program and move forward exclusively with cars," said Eric Meyhofer, the leader of Uber's self-driving technology program, in a statement to The Verge. Personnel from the truck division will be folded into the company's self-driving car efforts.

Uber has been scaling back its program in other ways, too. Uber completely abandoned its extensive testing program in Arizona in May. Then, earlier this month, the company laid off its safety drivers in Pittsburgh and San Francisco—around 100 people in total—and invited them to re-apply for 55 newly created "mission specialist" jobs doing similar work.

Uber resumed testing in Pittsburgh this week—but in a very limited way. Initially, Uber will only be operating its cars in manual mode to gather sensor data. And Citylab's Laura Bliss reported earlier this month that Uber is planning to limit initial testing to a handful of hand-picked routes.

While Uber scales back its testing, other companies have been charging forward. Waymo's self-driving trucks began hauling cargo earlier this year. And a number of startups are also working on autonomous or semi-autonomous trucking technology.