A report published Friday from the New York Times shows that Apple's self-driving car might be hitting some (figurative) roadblocks. Though the project has been kept tightly under wraps, anonymous sources closely tied to its development told the Times that Apple has "shuttered parts of its self-driving car project and laid off dozens of employees."

The project, nicknamed "Titan," began about two years ago but has faced developmental challenges as staff grew. The Times reported:

The team also pulled in staff members from other divisions across Apple, growing to more than 1,000 employees in about 18 months. But as the project grew rapidly, it encountered a number of problems, and people working on it struggled to explain what Apple could bring to a self-driving car that other companies could not, according to the people briefed on the project.

Apple employees were reportedly told "the [most recent] layoffs were part of a 'reboot' of the car project, the people briefed on it said." Another anonymous source told Quartz that Apple will focus largely on batteries and will continue to hire battery technicians. 

Apple faces competition from companies like Alphabet (Google's parent company), Tesla, Uber, BMW, General Motors, and Fiat Chrysler, which are each independently pursuing ways to invest in or manufacture self-driving cars. Tesla CEO Elon Musk told a crowd in June that he believed Apple would be "a direct competitor" in the race to produce a self-driving car, and that they would have a self-driving car manufactured by 2020.

"They should have started production sooner. It's a missed opportunity," he said.