Iran Threatens US with Sleeper Cells, Lone Wolves, and Cyberattacks

Federal authorities warn of potential retaliation from Iran following recent strikes on its leadership.

Published on Mar. 10, 2026

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With U.S. and Israeli forces continuing offensive strikes on Iran, federal counterterrorism authorities are warning that the desperate theocracy could launch retaliatory strikes on American soil using sleeper cells, affiliated Iranian terrorist groups, lone wolf sympathizers or targeted cyberattacks. Authorities have detected a new broadcast of a likely encoded sequence that could be "an operational trigger" for "sleeper assets" potentially on U.S. soil, though no credible specific threat has been found yet.

Why it matters

Sleeper cells and lone wolf attacks from Iran-linked groups have long been a concern for U.S. counterterrorism officials, especially given the heightened tensions following recent strikes on Iranian leadership. This latest warning highlights the ongoing threat and the need for vigilance from law enforcement and the public.

The details

Within days of the killing of Iranian Supreme Leader Ayatollah Ali Khamenei on Feb. 28, cryptic messages were broadcast globally on a new shortwave radio frequency, using the Persian word for "attention" and then reading a seemingly random string of numbers. Federal authorities warned local law enforcement that this was likely an encoded sequence that could be "an operational trigger" for "sleeper assets" potentially on U.S. soil. While no credible specific threat has been found, authorities are on heightened watch for potential retaliation from Iran, which has previously tried to hire assassins to kill U.S. officials.

  • On February 28, Iranian Supreme Leader Ayatollah Ali Khamenei was killed.
  • Within days of Khamenei's death, the cryptic radio broadcast was detected.

The players

Horace Frank

Former head of counterterrorism for the Los Angeles police and a retired assistant chief.

Jim McDonnell

Chief of the Los Angeles Police Department.

Syed Rizwan Farook

A U.S. citizen who, along with his Pakistani-born wife Tashfeen Malik, carried out the 2015 San Bernardino terrorist attack.

Ndiaga Diagne

A 53-year-old man who donned an Iran-themed outfit and killed three people and wounded 13 on Austin's bar strip before being fatally shot by police.

Rodney Scott

Customs & Border Patrol Commissioner who warned that "thousands of Iranian nationals have been documented entering the United States illegally" between 2022 and 2025.

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What they’re saying

“Sleeper cells have always been a concern when it comes to Iranians and their proxies. This isn't new, but given the situation, some of their proxies are feeling a lot more desperate.”

— Horace Frank, Former head of counterterrorism for the Los Angeles police and a retired assistant chief (The Tribune)

“We are at a heightened level of awareness. Lone wolves in our experience have been our concern.”

— Jim McDonnell, Chief of the Los Angeles Police Department (The Tribune)

What’s next

The judge in the case will decide on Tuesday whether or not to allow Ndiaga Diagne out on bail.

The takeaway

This case highlights growing concerns in the community about repeat offenders released on bail, raising questions about bail reform, public safety on US streets, and if any special laws are needed to govern autonomous vehicles in residential and commercial areas.