Terrorist Threat in the US: ‘Stay on High Alert’

A chief concern following the launch of Operation Epic Fury is Iranian-backed terrorist cells in the United States, security experts are warning.

It is impossible to know who crossed the border during the four years of the Biden administration, “but we do know there were a number of folks on the terrorist watch list,” said Victoria Coates, vice president of the Davis Institute for National Security and Foreign Policy at The Heritage Foundation.

It is critical, Coates warned, that “everybody pay attention right now. Watch. If you see something, say something.”

U.S. Customs and Border Protection encountered nearly 400 illegal aliens with “terrorism-related records” between ports of entry during the Biden administration, according to the agency’s data.

Additionally, about 2 million “known gotaways” crossed the border to enter the U.S. during the four years of Joe Biden’s presidency, according to the House Homeland Security Committee.

“So, it is entirely possible in those millions of folks who came across … that there were Hezbollah sleeper cells coming up from Venezuela, which we know Nicolas Maduro was pushing them to do, and that they could be here in the United States,” Coates told The Daily Signal.

“These folks aren’t geniuses, but they’re deeply, deeply dangerous, and they can spring up anywhere,” she said. “And so, my biggest concern is actually here at home.”

Following the launch of the U.S.-Israel attack, Iran is a bit like “a wild animal in a cage—cornered, boxed in,” Jacob Olidort, director of American Security at the America First Policy Institute, told The Daily Signal.  

“Out of desperation, you know, it’s hard to anticipate exactly fully how Iran might escalate, but I think some of the known would be more barrages and drones. It would also be activating its sleeper cells,” Olidort said.  

While Olidort urged “prudence and caution,” he said U.S. intelligence likely has “broad awareness within the United States as well, I suspect, of [Iranian-backed] activities and threats.” 

On Sunday, just after the U.S. and Israel launched their joint attack on Iran, police shot and killed a man wearing a “Property of Allah” sweatshirt and a shirt with an Iranian flag design after the man allegedly carried out a mass shooting in Austin, Texas.

The shooting left two people dead and another 14 injured at a bar near the University of Texas–Austin campus, the New York Post reports. The suspected shooter, identified as 53-year-old Ndiaga Diagne, entered the U.S. from Senegal in 2000 and became a U.S. citizen in 2013, according to The Post.

The FBI is investigating the incident as a possible act of terrorism following U.S. actions in Iran, according to multiple sources.

Department of Homeland Security Secretary Kristi Noem said Saturday that she is in “direct coordination with our federal intelligence and law enforcement partners as we continue to closely monitor and thwart any potential threats to the homeland.”

Last June, a DHS National Terrorism Advisory System bulletin warned of the possibility of domestic threats on the day the U.S. bombed several of Iran’s nuclear facilities.

“The ongoing Iran conflict is causing a heightened threat environment in the United States,” the June 22, 2025, bulletin stated. “US law enforcement has disrupted multiple potentially lethal Iranian-backed plots in the United States since 2020. During this timeframe, the Iranian government has also unsuccessfully targeted critics of its regime who are based in the Homeland for lethal attack.”

Correction: This piece was corrected after publication to clarify that police killed the Austin mass shooting suspect.