U.S. intelligence officials have intercepted encrypted communications believed to have originated in Iran that could serve as an "operational trigger" for sleeper cells operating abroad, according to a federal alert issued to law enforcement agencies.
The alert, reviewed by ABC News, references "preliminary signals analysis" of a transmission described as "likely of Iranian origin" that was sent to multiple countries shortly after the death of Iran's supreme leader, Ayatollah Ali Khamenei.
Khamenei was killed Feb. 28 during a joint U.S.-Israeli strike.
Officials say the intercepted transmission was encoded and appeared to be intended for "clandestine recipients" who possess the encryption key.
Messages of that type are usually used to pass instructions to "covert operatives or sleeper assets" without relying on the internet or cellular communications.
According to the alert, it is possible the signals could "be intended to activate or provide instructions to prepositioned sleeper assets operating outside the originating country."
"While the exact contents of these transmissions cannot currently be determined, the sudden appearance of a new station with international rebroadcast characteristics warrants heightened situational awareness," the alert said.
Authorities emphasized that the alert does not identify a specific threat location. It states there is "no operational threat tied to a specific location," but urges law enforcement agencies to increase monitoring of suspicious radio-frequency activity.
If confirmed, the communications could reinforce concerns raised by law enforcement officials following the U.S. and Israeli strikes on Iran that sleeper cells positioned throughout Western countries could be used in retaliatory attacks.
Nicole Weatherholtz ✉
Nicole Weatherholtz, a Newsmax general assignment reporter covers news, politics, and culture. She is a National Newspaper Association award-winning journalist.
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