Eligible Receiver 97 was a U.S. Defense Department exercise conducted under what is known as the No-Notice Interoperability Exercise Program. The exercises were held June 9–13, 1997 and included participants such as the National Security Agency (which acted as the Red Team), Central Intelligence Agency, Defense Intelligence Agency, Federal Bureau of Investigation, National Reconnaissance Office, Defense Information Systems Agency, Department of State, Department of Justice, as well as critical civilian infrastructure providers such as power and communication companies. The simulated cyber attack led directly to the formation of the United States Cyber Command.