The New York Police Department issued an internal memo to officers reminding them they are not allowed to assist federal immigration authorities, the New York Daily News reported.

The memo was issued Saturday ahead of President Donald Trump's inauguration by NYPD Police Commissioner Jessica Tisch, the Daily News said.

"The fact that a person is present in the United States without lawful authorization is a civil matter, not a crime," Tisch wrote.

Police officers are not permitted to contact federal authorities to tell them where an individual is located and cannot detain them and cannot use police department facilities to help Immigrations and Customs Enforcement, Tisch said.

Any officer who encounters ICE conducting an immigration raid must inform the Operations Division of the NYPD, Tisch said. Officers cannot release anyone from police custody without authorization from the city lawyers and the officers’ operations command, even if ICE has a warrant, Tisch said.

The Mayor's Office of Immigrant Affairs issued a memo before Trump took office, reminding all city agencies of sanctuary city laws, Rebecca Engel, Director of Policy and Legislative Affairs at the office said at a City Council oversight hearing last week, the Daily News said.

The city's law department also held a briefing to give city attorneys a refresher on city laws in advance of Trump’s plans for mass deportations, the Daily News reported.

New York City's public schools held a training session on city laws for principals and administrators in case federal authorities request access to school grounds, the Daily News said.

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