Microsoft employees are putting pressure on their management to cancel a contract with U.S. Immigration and Customs Enforcement, part of a backlash against the agency’s policy of separating children from their families at the U.S. border.

In an open letter to Microsoft CEO Satya Nadella sent today, employees demanded that the company cancel its $19.4 million contract with ICE and instate a policy against working with clients who violate international human rights law. The text of the employee letter was first reported by the New York Times and confirmed by Gizmodo.

“We believe that Microsoft must take an ethical stand, and put children and families above profits,” the letter, signed by Microsoft employees, states. “We request that Microsoft cancel its contracts with ICE, and with other clients who directly enable ICE. As the people who build the technologies that Microsoft profits from, we refuse to be complicit. We are part of a growing movement, comprised of many across the industry who recognize the grave responsibility that those creating powerful technology have to ensure what they build is used for good, and not for harm.”