Elon Musk has begun laying off Twitter employees, culling the social media service’s 7,500-person work force a little over a week after completing his blockbuster buyout.

Twitter employees were notified in a company-wide email on Thursday that the layoffs were set to begin. Workers were instructed to go home and not go to the offices on Friday as the cuts proceeded. The message, which came from a generic address and was signed “Twitter”, did not detail the total number of layoffs.

“In an effort to place Twitter on a healthy path, we will go through the difficult process of reducing our global work force,” the email said. “We recognise 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.”

About half of Twitter’s workers appeared set to lose their jobs, according to previous internal messages and an investor, though the final count may take time to become clear. As the email landed in employee inboxes on Thursday evening, workers posted salute emojis and heart emojis in Slack, the messaging service. Later in the evening, some employees said they had lost access to the company’s systems, a possible prelude to being laid off.

Rumours of impending layoffs had been swirling at the company. On Wednesday, employees took note of a Slack message that suggested 3,738 people could be laid off. The message noted that changes could still be made to the list, according to the email.

On Wednesday evening, some employees circulated a “Layoff Guide” with tips on corporate surveillance and employment rights. One worker created software to help colleagues download important emails and documents. He was later fired, he said.

On Thursday, workers got other signals that their workplace was changing. Twitter’s “Days of Rest”, which are monthly days off so employees can rest and recharge, were removed from their calendars, two people with knowledge of the matter said. Some workers also noticed that the employee directory had been taken offline.

“Has the red wedding started?” one employee wrote on Slack, a reference to a massacre scene in the Game of Thrones. Nine minutes later, the company sent the email informing workers of the layoffs. Employees who will keep their jobs would receive a message saying so on their corporate accounts, the message said, while employees being laid off would be notified on their personal accounts.

Under the terms of his deal to acquire Twitter, Musk agreed to keep employee compensation and benefits the same for one year. Twitter workers are typically paid at least two months’ salary and the cash value of equity they were scheduled to receive within three months of a layoff date, according to an internal benefits summary.

At Twitter’s headquarters in San Francisco late on Thursday, some employees milled about in one of the building lobbies, still wearing their corporate badges that grant them access to the premises. Some had drinks in hand from a bar attached to Twitter’s office and refreshed their phones for news about cuts.

With workers kept out of Twitter’s offices on Friday, those who are laid off will be blocked from taking any items from the company. “To help ensure the safety of each employee as well as Twitter systems and customer data, our offices will be temporarily closed and all badge access will be suspended,” the email said.

This also means that many Twitter employees are likely to find out about their job status from their homes.

“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.”

Early Friday morning, the company began to notify some employees that they had been laid off. The emails varied by an employee’s region or country. One New York-based worker received an email saying their job had been “impacted” but that they would remain employed through a separation date in early February.

“During this time, you will be on a Non-Working Notice period and your access to Twitter systems will be deactivated,” read the email, which too was signed “Twitter”. Employees would receive details on severance “within a week”.

Some other Twitter employees learned via email that they had not been laid off. That email said the company’s offices would reopen on Monday, and that there would be more information to share next week.

Musk “is looking forward to communicating with everyone about his vision for the company soon”, it read.

Musk and Twitter did not immediately respond to requests for comment.

Twitter’s layoffs are unlikely to be the largest in the tech industry by total number. The computer manufacturer HP cut 24,600 of its employees, about 7.5 per cent, in 2008. It later cut tens of thousands more, reaching about 30 per cent of its work force.

Jesse Lehrich, a founder of Accountable Tech, an industry advocacy organisation, said the layoffs amounted to an arbitrary purge just days before the midterm elections on Tuesday.

“There is nothing visionary or innovative about summarily firing” workers by email, he said, especially people who have “specialised expertise and deep institutional knowledge” and before Musk “even seems to have a basic grasp of the business”.

While federal and California laws require companies to provide advance notice of mass layoffs, it was not clear whether Musk had done so. A spokesman for California’s Employment Development Department said on Thursday evening that it had received no such notices from Twitter, which is based in San Francisco and is expected to report mass layoffs to the agency.

(New York Times News Service)