Enemy within: Counterterrorism experts fear sleeper cells could be poised inside US

U.S. counterterrorism agencies monitor suspected sleeper cells following joint strikes on Iran that killed Ayatollah Khamenei ...

Iran's threats on U.S. soil: sleeper cells, lone wolves, cyberattacks and eerie numbers code

Federal authorities warn that Iran could launch retaliatory strikes on American soil using sleeper cells, lone wolf sympathizers or cyberattacks.