SAN FRANCISCO — Facebook overhauled its structure on Tuesday into three new divisions and shuffled the leadership of its key products, in one of its biggest reorganizations.

The moves happened at the direction of Facebook’s chief executive, Mark Zuckerberg, said a person with knowledge of the changes, who asked not to be identified because he was not authorized to discuss them. The reorganization was intended to streamline the company and clarify who oversees what after a long period of growth and numerous acquisitions, according to another person involved.

But the changes were accelerated after Facebook faced criticism recently for its lack of protections around user data, following revelations that the information of millions of its members had been harvested by a political consulting firm with ties to the Trump campaign, said one of the people. Mr. Zuckerberg was adamant about not firing any senior executives, despite pressure to make prominent changes, this person said.

Facebook told employees about the reorganization in an internal companywide memo on Tuesday. Recode earlier reported the changes, which were confirmed by a Facebook spokesman.