SAN FRANCISCO - Elon Musk is beginning mass layoffs at Twitter, sharply reducing the company's workforce of 7,500 and beginning his wholesale overhaul of the company, as he took aim at a work environment he has decried as too relaxed.

"Team, In an effort to place Twitter on a healthy path, we will go through the difficult process of reducing our global workforce on Friday," the email to workers said, instructing them of how they may learn whether their position was affected. "We recognize that this will impact a number of individuals who have made valuable contributions to Twitter, but this action is unfortunately necessary to ensure the company's success moving forward."

The email kicked off an anxious wait for many employees, who would not find out immediately whether they would be affected. Instead, it said that by 9 a.m. Pacific time Friday, workers would receive an email with the subject line: "Your Role at Twitter."

Those keeping their jobs would be notified on their company email. Those losing them would be told via their personal email.

And anyone who did not receive an email by 5 p.m. Pacific was told to follow up with the company.

Twitter said its offices would be closed Friday.

"We acknowledge this is an incredibly challenging experience to go through, whether or not you are impacted," the email continued. "We are grateful for your contributions to Twitter and for your patience as we move through this process."

It was the Musk team's first official companywide communication with his staff.

The layoffs decision came after a week-long assessment of Twitter, where Musk and his deputies imposed a product freeze that stopped development on Twitter's internal projects, brought in Tesla engineers to review Twitter's code, and left workers anxiously waiting in a vacuum of information on the company's direction and leadership.

Musk was expected to proceed with plans to lay off about 50 percent of Twitter's staff, according to people familiar with the matter, who spoke on the condition of anonymity to candidly discuss confidential plans.

The layoffs were expected to affect the sales, trust and safety, marketing, product, engineering and legal teams - targeting the company across the board.

The layoffs were not expected to significantly impact the operational capabilities of the trust and integrity workforces, which work on protecting U.S. elections, according to a person familiar, who spoke on the condition of anonymity to discuss the layoffs.

Musk assumed ownership of Twitter last week after striking a deal to buy the website for $44 billion this spring, before angling to exit the purchase and then reentering the agreement as a trial date in a court battle loomed.

Musk is CEO of the new company. His deputies include his attorney, Alex Spiro, investor David Sacks, and Jared Birchall, who manages Musk's family office.

Twitter employees prepared Thursday for what seemed like an inevitability, refreshing their internal tools such as messaging apps to learn the latest - as the possibility of losing their jobs loomed over them.

But information remained sparse.

At Twitter's offices, employees said tearful goodbyes, exchanged contact information and tried to make their documentation easily accessible for the staff who were to remain.

They wanted to ensure their colleagues could keep the site running in their absence.

Before Musk took over the site, Twitter had already planned broad layoffs, which would have affected up to a quarter of the staff, according to people familiar the plans. The Washington Post reported previously the company's board was planning to cut thousands of jobs as part of an effort to save $700 million in labor costs.

Will Oremus and Cat Zakrzewski contributed to this report.