Elon Musk will begin laying off Twitter employees on Friday morning, according to a memo sent to staff, as several Twitter employees file a class action lawsuit alleging the layoffs are in violation of labor law.

On Thursday night and into Friday morning, some Twitter employees began posting on the platform that they had already been locked out of their company email accounts ahead of the planned layoff notification.

The email added that “to help ensure the safety” of employees and Twitter’s systems, the company’s offices “will be temporarily closed and all badge access will be suspended.”