Sources have told CNBC over 200 people have been fired this week from Apple's Project Titan group.
A spokesperson for the tech company confirmed the layoffs to the business news channel. The person added "as the team focuses their work on several key areas for 2019" some groups have been moved to other areas within the company, such as machine learning.
The representative also noted there is a "huge opportunity with autonomous systems, [and] Apple has unique capabilities to contribute, and ... this is the most ambitious machine learning project ever".
Both the firings and redeployment of headcount are believed to be instigated by Doug Field, an executive brought back to Apple in August 2018 after spending time as Tesla's vice president of engineering.
This isn't the first time Apple has slimmed down the number of people working on Project Titan. Reports indicate the tech giant initially ran the secret project with an eye on one day making its own self-driving car.
As things progressed, the scope has narrowed. When Tim Cook, Apple's CEO, finally confirmed Project Titan's existence in 2017, he stated the company was focussing on autonomous driving technology, and described it as "the mother of all AI projects".