A federal agent from U.S. Citizenship and Immigration Services went to a public school in Maspeth, Queens and allegedly asked about a student, according to Mayor Bill de Blasio's office.

On Saturday night, Eric Phillips, a spokesman for Mayor de Blasio, Tweeted, "Mayor's been briefed on a fed immig agent showing up at Queens' PS58 Thurs. asking about a 4th grader. School turned him away. A 4th grader."

The agent apparently did not have a warrant and was turned away by a school safety agent and administrator.

"All students, regardless of immigration status, are welcome in NYC public schools, and parents should rest assured that we will do everything on our power to protect students, staff and families," Schools Chancellor Carmen Farina said in a statement. "The federal agent was turned away—we're looking into this incident and are providing schools with additional information on our protocol and more trainings."

According to the Department of Education's protocol, "Non-local law enforcement officers, including ICE officers, may only obtain access to school facilities or students in school under one of the following circumstances: with consent; with proper warrants; or under exigent circumstances," and "DOE does not consent to non-local law enforcement accessing school facilities in any circumstances, and principals and other school personnel may not give consent."

@mgeorge4NY We don't know. He left when school workers didn't assist in locating the child. No warrant. — Eric Phillips (@EricFPhillips) May 14, 2017

As fears escalated about a crackdown on immigrants after President Donald Trump took office, Farina told immigrant students that they would be protected in January. Two months later, she offered an update to parents of schoolchildren, "to reaffirm our commitment to protecting the right of every student in New York City to attend public school, regardless of immigration status," with bolded points like "Federal agents, including Immigration and Customs Enforcement (ICE) will not be permitted to enter schools, except when absolutely required by law" and "DOE staff will not release student information unless absolutely required to by law."