Washington — The arrests of eight Tajik nationals with alleged ties to ISIS have renewed concerns about the terrorist group or its affiliates potentially carrying out an attack in the U.S. 

The arrests in Los Angeles, New York and Philadelphia came as U.S. officials have been warning for months about the potential for a terror attack and as the U.S. has been on heightened alert. 

"I see blinking lights everywhere I turn," FBI Director Christopher Wray testified to the Senate Judiciary Committee in December, telling lawmakers, "I've never seen a time where all threats were so elevated all the time." 

In April, he warned that human smuggling operations at the U.S.-Mexico border were bringing in people potentially connected to terror groups. 

On Friday, the State Department announced the U.S. and Turkey are imposing sanctions on three individuals with links to ISIS who are involved in trying to facilitate travel to the U.S. 

Republican lawmakers have used the arrests as the latest flashpoint in their call for stricter border measures. 

GOP Sen. Lindsey Graham of South Carolina sent a letter to Majority Leader Chuck Schumer, a New York Democrat, and Minority Leader Mitch McConnell, a Kentucky Republican, requesting a classified briefing for all senators detailing ISIS threats against the U.S. 

"I believe that the threat is urgent," the South Carolina Republican wrote, asking for a briefing before the Senate goes on recess at the end of next week. 

A spokesperson for Graham said they have not heard back. Spokespeople for Schumer and McConnell did not immediately return requests for comment. 

In a speech on the Senate floor Wednesday, Sen. James Lankford of Oklahoma called on officials "to wake up" and criticized the border screening process. 

"We are literally living on borrowed time," he said. "What's really happening day to day is that individuals that are crossing our border, we're hoping that the FBI can pick up any information on them after they're already released into the country." 

The Tajik migrants crossed the U.S.-Mexico border without proper documents and were given notices to appear in immigration court, according to a senior Department of Homeland Security official. Sources familiar with the operation said the individuals had been vetted by law enforcement upon entering the U.S., and there was no indication that they had ties to ISIS at the time. 

There was no active terror plot, but sources said information of concern came to the attention of law enforcement at least in part through a wiretap after the individuals were in the U.S. 

"It's only a matter of time before one of these individuals connected to a terrorist group is involved in something devastating on U.S. soil, and this administration will be responsible. How much longer will we let this madness continue?" Rep. Mark Green of Tennessee, the GOP chairman of the House Homeland Security Committee, said in a statement Wednesday. 

In an opinion piece he co-wrote before the arrests were reported, former acting CIA Director Michael Morell said officials' warnings should be taken seriously. 

"Combined, the stated intentions of terrorist groups, the growing capabilities they have demonstrated in recent successful and failed attacks around the world, and the fact that several serious plots in the United States have been foiled point to an uncomfortable but unavoidable conclusion," the piece published in Foreign Affairs said. "Put simply, the United States faces a serious threat of a terrorist attack in the months ahead. 

Andres Triay, Robert Legare and Camilo Montoya-Galvez contributed reporting. 

In:
• ISIS
• U.S. Immigration and Customs Enforcement
• Terrorism
• FBI

Caitlin Yilek

Caitlin Yilek is a politics reporter at CBSNews.com, based in Washington, D.C. She previously worked for the Washington Examiner and The Hill, and was a member of the 2022 Paul Miller Washington Reporting Fellowship with the National Press Foundation.

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