U.S. officials have intercepted encrypted communications believed to have originated in Iran that could serve as an “operational trigger” for sleeper assets outside the country, according to a federal alert sent to law enforcement agencies.
The alert, reviewed by ABC News, cites “preliminary signals analysis” of a transmission “likely of Iranian origin” relayed across multiple countries shortly after the Feb. 28 U.S.-Israeli strike that killed Iran’s supreme leader, Ayatollah Ali Khamenei.
Officials said the message was encoded and appeared intended for “clandestine recipients” possessing the encryption key, a method commonly used to deliver instructions to covert operatives or sleeper assets without relying on internet or cellular networks.
Authorities warned the transmissions 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.
The notice stated there is currently “no operational threat tied to a specific location,” but directed law enforcement agencies to increase monitoring of suspicious radio-frequency activity.
