Amazon CEO Andy Jassy recently announced a return-to-office mandate for employees currently working from home.

The new mandate requires employees to work from the office at least three days a week starting May 1.

And employees were furious. Those affected by the call to office have been sounding off about the sudden policy change, including spamming an internal website with messages that show their staunch opposition to the change.

A group of tech workers created a Slack channel, drafting an internal petition pushing back against Jassy’s new mandate.

The group has since amassed 16,000 members and around 5,000 employees have signed the petition as of late Tuesday.

Employees also took to Amazon’s internal news feed for employees, known as Inside Amazon, with workers commenting on a recording of Jassy’s announcement.

One worker said, “By arbitrarily forcing return-to-office without providing data to support it and despite clear evidence that it is the wrong decision for employees, Amazon has failed its role as earth’s best employer. I believe this decision will be detrimental to our business and is antithetical to how we make decisions at Amazon.”

Working from home benefits include less strict dress codes, more boons for those dealing with mental health struggles, and freedom from a commute which can be both costly and time consuming. Working from home has positive impacts on both employees and the environment, and employers can benefit from improved mental health, productivity and timeliness.

The employees’ petition includes a number of data points and studies which highlight the benefit of working from home, including those listed above.