An encrypted communication believed to have originated in Iran may have been intended to activate “sleeper assets” outside the country, according to a federal alert sent to law enforcement agencies.
The alert cites preliminary signals analysis of a transmission “likely of Iranian origin” that was relayed across multiple countries shortly after the death of Ayatollah Ali Khamenei, Iran’s supreme leader. Khamenei was killed in a U.S.-Israeli attack on Feb. 28, ABC News reports.
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The federal alert says the transmission was encrypted and likely intended for “clandestine recipients” who already possess the encryption key. Officials noted that messages sent this way can be used to pass instructions to “covert operatives or sleeper assets” without relying on internet or cellular networks.
The transmissions could possibly be “intended to activate or provide instructions to prepositioned sleeper assets operating outside the originating country,” the alert said.
The alert says the exact contents of the transmission remain unknown, but officials said the sudden appearance of a new station with international rebroadcast characteristics raised concern.
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“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 alert does not identify a specific operational threat tied to any location, but it instructs law enforcement agencies to increase monitoring of suspicious radio-frequency activity.
If the information in the alert is confirmed, it would align with concerns raised by law enforcement officials after U.S. and Israeli strikes on Iran that sleeper cells operating in Western countries could be used for retaliation.
