Nationwide immigration raids are underway in several major cities, including in New York.

Public officials spoke out this weekend and urged residents to resist authorities and know their rights. New York City Mayor Bill de Blasio says immigration and customs enforcement agents have already been spotted in Manhattan.

De Blasio posted on social media that his administration has received reports of attempted but unsuccessful Immigration and Customs Enforcement action across parts of the city.

"It's not about public safety. I'm in a city where we have become safer every year, and we don't ask documentation status. Our police don't ask documentation status. They work with immigrant communities and it helps make us safer. So this is not about safety," de Blasio said.

Immigrant advocates say it's important to not let any ICE agent into your home unless they have a warrant signed by a judge.

President Donald Trump says immigration agents will specifically be looking for "bad players," but he says they'll also be targeting others who have come into the country illegally.

ICE officials say they are focusing the raids on 2,000 undocumented immigrant families who have orders of deportation.

ICE told News 12 in a statement, "As always, ICE prioritizes the arrest and removal of unlawfully present aliens who pose a threat to national security, public safety and border security."

The raids are expected to take place across at least nine major cities.