The southern border, fears of terrorism and the arrest of eight Tajik men

When eight Tajik men sought asylum at the U.S. southwest border months ago, federal authorities had no reason to doubt that they were desperate migrants fleeing a poor country in war-torn Central Asia.

But shortly after they entered the country, the FBI learned that they may have ties to the Islamic State and launched a counterterrorism investigation.

This was no ordinary investigation. Dozens of officers closely monitored the men as they traveled to various cities across the United States, officials said. The White House was regularly updated.

The office hoped to gather intelligence on a larger terror network, but growing concern about an imminent attack in at least one location led to the arrest of all eight men on immigration violations earlier this month, according to several U.S. officials who spoke on condition of anonymity about the sensitive investigation. The men have not yet been charged with any terrorism-related offenses.

This dramatic incident comes amid growing concern among U.S. officials, who have been warning for months that the conflict in Gaza and the unrest in Central Asia could spill over into the United States, most likely through small, radicalized groups acting on their own or through terrorists acting alone.

The new details about the FBI’s investigation and the decision to arrest the men underscore the flood of terrorist threats that national security agencies are currently facing, some from well-known international actors, others from new hot spots like Tajikistan.

Since the Hamas attacks in Israel on October 7, the FBI has received “more than 1,800 reports of threats or other types of tips or leads that are in some way related to or connected to the current conflict in Israel and Gaza,” Lisa Monaco, the deputy attorney general, said in a television interview in December. She added that many of the cases had been resolved without incident.

National security officials are deeply concerned about the speed at which these threats are advancing.

“As I look back over my career in law enforcement, I can hardly remember a time when so many different threats to our public and national security were so great at the same time, but that is the case today as I sit here,” FBI Director Christopher A. Wray told Congress this month, just days before the men were arrested.

An FBI spokeswoman declined to comment.

For years, Republicans and conservative media have been trumpeting the potential dangers posed by terrorists crossing the southwest border with tens of thousands of Latino migrants. These fears have largely proven unfounded.

It is still unclear whether the men were actually planning a terrorist attack — whether directed by the Islamic State or inspired by the extremist group — but the resources the FBI has devoted to the case underscore how seriously the agency continues to view the threat as a top priority.

The arrests come at a time when border security is attracting the highest political attention. The issue has become a major point of contention between President Biden and former President Donald J. Trump, who frequently refers to it as “migrant crime.”

Still, Representative Jim Himes, Democrat of Connecticut and ranking member of the House Intelligence Committee, urged that the incident be put into context, warning that the “number of deadly terrorist attacks committed by illegal immigrants crossing our southern border is zero” and that “the number of Americans injured by foreign-born terrorists who entered the country illegally is zero.”

Tajik supporters of the Islamic State – particularly within an offshoot known as ISIS-K – have played an increasingly prominent role in several recent terrorist attacks. In the past year alone, Tajiks have been involved in attacks in Russia, Iran and Turkey, and have also thwarted plots in Europe.

ISIS-K, or Islamic State Khorasan, was founded in Afghanistan in 2015 by disaffected members of the Pakistani Taliban who were then turning to a more violent version of Islam. The group’s number of fighters shrank by about half, to about 1,500 to 2,000, by 2021, due to a combination of American airstrikes and Afghan commando raids that killed many of its leaders.

The group experienced a second resurgence shortly after the Taliban overthrew the Afghan government that same year. During the U.S. military withdrawal from the country in August 2021, ISIS-K carried out a suicide attack at Kabul International Airport, killing 13 U.S. soldiers and up to 170 civilians.

Since then, ISIS-K has revived some of its global ambitions; experts say Tajiks make up more than half of its several thousand soldiers.

Russia is a frequent target, but ISIS-K has also vowed to attack Americans and the United States.

Most details of the FBI’s investigation remain classified, but interviews with several U.S. officials familiar with the case have provided additional insight.

Officials said the men entered the U.S. across the border in Southern California and Texas starting in 2023. They are all ethnic Tajiks, but at least one had a Russian passport. Some of the men may have known each other.

They made their way to Los Angeles, Philadelphia and New York, which have large Central Asian populations. When the FBI determined that the men may have had a connection to the Islamic State or sympathies with the group, the bureau was able to track down their whereabouts.

This sparked a major investigation reminiscent of the FBI’s post-9/11 efforts to track down several terror suspects in foiled plots, such as a 2009 attack on the New York City subway. In previous high-priority terrorism investigations, the FBI has relied on aerial surveillance and a key surveillance program without judicial authorization, known as Section 702, to gather intelligence.

The program authorizes the government to monitor the communications of selected foreign nationals abroad for intelligence purposes, even if those individuals are communicating with Americans.

The stakes were extremely high for the FBI and Mr. Wray. Had one of the men escaped and carried out a terrorist attack, the FBI would have been blamed for not arresting him sooner and would have faced scathing criticism from Republicans. But there is always a trade-off. Arrests make it harder to gather intelligence on a possible network.

In the case of the Tajiks, authorities said, it is still not known what the men did and whether they were directed by a terrorist group outside the United States or whether they were inspired to carry out an attack on their own.

Whatever the FBI eventually learned about the men’s movements prompted the bureau’s counterterrorism agents to pull them off the streets and arrest them on immigration charges. Agents from U.S. Immigration and Customs Enforcement and the FBI arrested the men, who were not named, in New York, Los Angeles and Philadelphia over the weekend of June 8.

The federal authorities have not disclosed public which led investigators to believe the men might be involved in terrorist activities. At the time, law enforcement said only that the men were arrested after unspecified “derogatory information” about them was discovered.

In another case, lawyers for a group of Uzbek nationals sued the U.S. government in federal court in February, alleging that migrants from the Central Asian country were deliberately detained at the southern border.

If the Tajiks are detained only on immigration charges and not on other federal crimes, they would almost certainly be deported, officials said.

In his testimony before Congress before the arrests, Mr. Wray hinted at the threat, even as the FBI quietly monitored the suspects.

“But now there is growing concern about the possibility of a coordinated attack here on the homeland, similar to the ISIS-K attack we saw on the Russian concert hall in March,” Wray said.

More than 130 people were killed in this attack near Moscow; several of the arrested suspects are Tajiks.

Julian E. Barnes And Glenn Thrush contributed to the reporting.