WASHINGTON >> The Justice Department is threatening to prosecute state and city officials who refuse to help the Trump administration carry out its immigration agenda, a provocative move that will reignite President Donald Trump’s first-term fight with liberals over “sanctuary” policies.

In a three-page memo, dated Tuesday and intended as guidance to all department employees for carrying out executive orders seeking to limit immigration and foreign gangs, interim leaders have told U.S. attorneys around the country to investigate law enforcement officials who decline to enforce such policies.

The memo commands state and local officials to cooperate with the department under the Constitution’s Supremacy Clause, or face criminal prosecution or civil penalties if they fail to comply.

It came as the Homeland Security Department prepared to make targeted raids in cities, including Chicago, with high numbers of immigrants in the country illegally.

The document underscored the central role the Justice Department will play in enforcing Trump’s hard-line immigration agenda. It also kick-started the pitched fight between the White House and states and cities that decline to comply with government directives that erupted in the first term. The Trump administration has long battled Democrats in sanctuary cities and counties — localities that refuse to hand over detained immigrants to federal authorities.

“Federal law prohibits state and local actors from resisting, obstructing, and otherwise failing to comply with lawful immigration-related commands,” wrote Emil Bove III, the department’s acting deputy attorney general and a former member of the president’s criminal defense team.

U.S. attorneys’ offices and officials from various branches of the department’s Washington headquarters “shall investigate incidents involving any such misconduct for potential prosecution,” Bove wrote, pointing to the same federal obstruction law used in the federal indictment against Trump that accused him of inciting the rioters who stormed the Capitol on Jan. 6, 2021.

The memo does not specify what actions local officials might take — or not take — that would justify such a prosecution. Local officials said the new policy was a political provocation that was unnecessary from a law enforcement perspective.

“As far as we know, no state or local officials are obstructing immigration enforcement,” said Lawrence Pacheco, a spokesperson for Attorney General Phil Weiser of Colorado, a Democrat. “The federal government — not local law enforcement — is responsible for enforcing federal immigration laws.”

Gov. Katie Hobbs of Arizona, a Democrat, said the memo was a distraction, adding, “I refuse to let political games get in the way of ensuring the safety and security of every Arizonan.”

Bove also warned localities against taking action to contradict the new federal policies and instructed the Justice Department’s civil lawyers to “identify state and local laws, policies and activities” that flout Trump’s executive orders and, “where appropriate, to take legal action to challenge such laws.”

The memo did not provide information about how extensive the planned raids or other actions would be. But it cited the fentanyl and opioid crisis, gang activity and crime by immigrants as justifications for the impending crackdown.

The department directed the deployment of the FBI’s joint terrorism task force, a vital asset used in investigating a broad array of international threats, to enforce Trump’s immigration orders. It is not clear whether the department intends to divert resources from other task force operations or whether the new mission is tied to the classification of gangs as terrorist organizations.

Sanctuary cities typically refer to jurisdictions that put some limits on their level of cooperation with federal agencies’ efforts to deport immigrants in the country illegally.

The Trump administration is aggressively targeting such jurisdictions for logistical reasons. Officials rely predominantly on local jails to pick up immigrants in the country illegally and try to deport them from the country. Immigration officials prefer picking up immigrants from jails, as opposed to arresting them in communities, because it is efficient and safer for officers.

But there are equally powerful political motives: Trump and Stephen Miller, the architect of his immigration crackdown, believe that picking a fight with liberal urban leaders is a win-win — allowing them to rile up their own base and to deflect blame if the mass deportation plan hits snags.

Even if the courts find the Trump administration’s aggressive executive orders on immigration to be constitutionally sound, that does not mean they will go along with attempts to punish state and local officials who refuse to carry them out, according to legal experts.

Printz v. United States, a 1997 Supreme Court ruling, found that county sheriffs could not be compelled to perform background checks on gun buyers. More broadly, the court barred the federal government from “requiring the states to address particular problems” or “command the states’ officers” under what is now known as the “anti-commandeering” doctrine.

“I don’t think I’ve ever heard a legal scholar say that the president has some special providence to order around state and local officials,” said Adam B. Cox, a professor at New York University’s law school. “Usually, if a state actor chooses to do nothing, that’s their constitutional prerogative.”

The Trump team, concerned that career department employees will not execute orders they deem to be immoral or unlawful, has considered transferring or instigating disciplinary actions against prosecutors who refuse to comply with commands.

It has also been making plans to transfer prosecutors to five U.S. attorneys’ offices near the border with Mexico and has discussed tactics to pressure recalcitrant departmental employees to do unpalatable jobs in an effort to encourage their mass departure, according to people familiar with transition planning.

In the memo, Bove ordered prosecutors to immediately step up immigration investigations against the most dangerous immigrants in the country illegally and warned employees that “any deviations” from that policy had to be cleared with supervisors.

In addition, prosecutors will be required to file an “urgent report” if they decide not to bring charges against serious offenders. The department will also begin tracking cases brought by each U.S. attorney’s office on a quarterly basis.

The memo also instructed other parts of the Justice Department — including the Bureau of Prisons, FBI, Drug Enforcement Administration and Bureau of Alcohol, Tobacco, Firearms and Explosives — to share any information they have regarding the immigration status of people they investigate or regulate.

Officials around the country are grappling with the disorienting opening barrage of Trump administration executive orders, memos and public statements about immigration that appear intended to intimidate, as well as instruct, local leaders.