As New York City prepared for immigration raids this past weekend, one homeless shelter provider took an unusual step.

Federal immigration agents are not allowed to enter shelters without a judicial warrant. Last week, the Social Services Department sent providers a reminder about the policy. But the city’s largest family shelter network, Win, advised immigrant families to leave shelters for a few days in case federal authorities showed up with a warrant, according to a source close to the organization.

“One of our jobs at Win is to keep our families safe,” said Win President and CEO Christine Quinn. “We take that job incredibly seriously and will not back down to anyone who threatens our clients, including the president of the United States.”

A city spokesman said immigration agents haven’t showed up at city shelters so far, but that any deviation from its policy stands to cause anxiety and fear among shelter residents.