Nearly half of FBI agents in the United States’ largest field offices have been reassigned to support immigration enforcement, according to new personnel data obtained by Senator Mark Warner.

The reallocation marks a significant shift in federal law enforcement priorities under the Trump administration, raising alarms about the potential impact on national security and other core FBI operations.

Warner, the top Democrat on the Senate Intelligence Committee, revealed that 45% of FBI agents in the 25 largest field offices are now working alongside Immigration and Customs Enforcement (ICE).

Nationwide, 23% of the FBI’s 13,000 agents are currently involved in immigration-related assignments, many spending more than half their workweek on such tasks.

Read more: Shutdown chaos: Trump cuts jobs, targets Blue-State workers

Immigration work displaces key national security operations

The redirected agents were previously assigned to divisions handling counterterrorism, cybercrime, violent crime, counterintelligence, espionage, and drug trafficking, areas long considered vital to US national security. Critics say the shift prioritizes political goals over public safety.

“When you pull a quarter of the FBI’s top agents off the front lines of fighting terrorists, spies, drug traffickers, and violent criminals, the consequences are clear,” said Warner. “Critical national security work gets sidelined, and our country is put at greater risk.”

The internal FBI data, first reported by The Washington Post, only accounts for agents whose duties are now primarily focused on immigration, suggesting that the true scale of the shift could be even greater. In some offices, over half of the staff may be engaged in support of ICE operations.

Related News

US court ruling threatens protected status of 60,000 migrants

Report reveals abuse of pregnant women, children at ICE facilities

The personnel changes reflect a broader effort by the Trump administration to accelerate immigration enforcement. The White House is reportedly targeting 3,000 arrests per day and is expanding detention capacity to hold more than 100,000 people.

The exact nature of the roles FBI agents are now performing with ICE remains unclear. The Department of Homeland Security, ICE, the FBI, and the Department of Justice all declined to comment.

Former FBI agents warn of mission drift, safety risks

Former FBI agent and civil liberties advocate Mike German called the reassignment “unprecedented", noting that immigration enforcement is not within the traditional mandate of the bureau. He warned that some agents may not be properly trained for ICE’s operational methods, which can involve chaotic and aggressive tactics.

“Jumping in an SUV with armed men and roaming the streets is inherently dangerous and outside the FBI’s investigative training,” German said, as reported by The Guardian. He added that the reassignment could serve to identify agents loyal to the administration’s immigration policies versus those who are not.

German also expressed concern about the FBI’s diminished capacity to investigate public corruption and white-collar crimes, areas often left unaddressed by state and local law enforcement.

Concerns over morale, oversight, and long-term impact

Internal reports suggest growing frustration and low morale among FBI personnel as national security cases and complex investigations are delayed or deprioritized. Kenneth Gray, a former FBI agent and now professor at the University of New Haven, compared the shift to the bureau’s reorganization after the 9/11 attacks, when counterterrorism became its primary focus.

“The bureau can withstand a temporary change in its priorities,” Gray told The Washington Post. “But if agents are permanently diverted from counterterrorism, foreign intelligence, or cybercrimes to immigration, that may come back to bite us big time. The next 9/11 might happen because we weren't watching.”

Still, Gray noted that if the shift is temporary while the US Department of Homeland Security recruits new ICE officers, the FBI could recover.

DOJ defends shift amid political scrutiny

At a recent Senate hearing, US Attorney General Pam Bondi defended the redirection of FBI agents to assist in immigration enforcement, pushing back against accusations that the Justice Department was being weaponized for political aims.

“FBI agents are working daily with DHS on keeping Americans safe and getting illegal aliens out of our country,” Bondi said.

But experts warn that the change in priorities may have long-term consequences, both for public trust in the FBI and for its core mission in safeguarding the United States against internal and external threats.