Nassau County police will be granted federal authority to help arrest and deport illegal criminal migrants under an agreement with the Trump administration, officials announced Tuesday.

Nassau County Executive Bruce Blakeman jumped at the chance to have his police department participate in the program when US Immigration and Customs Enforcement reached out and sought cooperation to arrest and deport illegal aliens committing crimes.

“We don’t want illegal immigrants roaming around our community committing crimes. We don’t want them in our community,” Blakeman told The Post.

“Our detectives will arrest illegal immigrants engaged in criminal activity. We want to make sure these people are locked up and deported.”

Under the arrangement, ICE will “cross-designate” or delegate authority to 10 Nassau County detectives to enforce immigration law, as well as perform their other policing duties.

ICE has the authority to grant local law authorities federal immigration enforcement powers under its 287(g) program.

The county will receive federal funding for assisting with immigration enforcement.

As part of the agreement, Nassau County will also detain a suspected illegal immigrant for up to 72 hours and will give ICE a permanent presence at the county jail, Blakeman said.

Blakeman’s office noted that ICE was evicted from the county jail under his Democratic predecessor, Laura Curran.

“We are very grateful that President Trump and [border czar] Tom Homan are serious about a problem that has plagued our region,” said Blakeman, who claimed ICE did not seek such cooperation during the Biden administration.

Nassau County will become the largest police force in New York state, and among the largest in the country, to be granted special powers to crack down on illegal immigration, he said.

The Republican said he found it “bizarre” that other local governments and police forces might refuse such an offer.

The program will help break up migrant gangs and theft rings that have terrorized Long Island neighborhoods, he said.

During a press conference later Tuesday, Bryan Flanagan, acting deputy field office director for ICE, thanked Nassau for the partnership to bolster public safety.

“By providing 72 hour bed space, Nassau County will enable ICE to house the transfer of potentially dangerous alien offenders in a safe and secure environment, thus providing security to our officers, the detainees and the public at large. Protecting public safety remains at the heart of everything we do as law enforcement officers,” Flanagan said.

The agreement is an expansion of the Nassau County Police Department’s current cooperation with ICE, said Police Commissioner Patrick Ryder.

Even before the agreement, Nassau officers enforced judicial warrants issued by ICE.

“There is now a change in that when it comes to the administrative side of items. If we make an arrest and I’m going to let somebody out on an appearance ticket because of no bail at my station house, I will be notifying ICE that this person is here undocumented, and that they will be able to come and pick that individual up,” Ryder said.

“If that individual is not available, we will use the ten cross designated detectives or task force members to go in and  bring those people to the jail, where they will be held on the ICE detainer.”

During the joint event, Blakeman emphasized the Nassau-ICE partnership will focus on illegal immigrants who are committing crimes, and that undocumented residents who are law-abiding should not be alarmed.

“This isn’t about raids. This is targeted enforcement of our laws based here in the state of New York. People who have committed crimes here and have violated federal laws by being in the United States illegally,” Blakeman said.

He gave examples of horrific crimes allegedly committed by illegal immigrants, including the rape of a 5-year-old by a Honduran migrant last year, others peddling deadly fentanyl and burglars who cut their monitoring bracelets while out on bail and then vanished.

“If we didn’t initiate this program, they would probably come back here because criminals are opportunists. And if they know that if there are no consequences for any criminal activity, they do it over and over again,” said the county executive.

Fifty jail cells will be set aside for illegal immigrants involved in crimes, said Blakeman.

Immigration advocates and civil libertarians slammed the decision to turn Nassau cops into ICE agents

“Nassau County Executive Bruce Blakeman’s plan to turn certain local law enforcement officers into de facto ICE agents is a dangerous decision that will undermine public safety and needlessly enable ICE’s cruelty,” New York Civil Liberties Union regional director Susan Gottehrer said.

“Any partnership with ICE sends the message to immigrant communities that local law enforcement is not there to protect them, but is instead targeting them for deportation. Immigrants enrich Nassau County’s culture, economy, and communities — they deserve to feel safe and protected.”

 The civil liberties group questioned the legality of the program, hinting it will be challenged in court.

“Local law enforcement have no place doing ICE’s bidding and enforcing laws outside their expertise — in fact, New York state law prohibits officers from holding someone for civil immigration purposes,” Gottehrer said.

A Latino immigration advocacy group called the Nassau-ICE alliance “dangerous, misguided and unlawful.”

“Local law enforcement should protect and serve all residents. Engaging in federal immigration enforcement to turn people over to an out-of-control federal government seeking to raid homes, schools, churches, and workplaces of Long Islanders with impunity will cause lasting damage to the community,” said Lourdes Rosado, president and general counsel of LatinoJustice PRLDEF.