According to Matthew Roberts, director of communications for the Arizona secretary of state, in late May, Arizona officials took the statewide voting registration system offline after the FBI alerted the Arizona Department of Administration that there was a credible cyber threat to the voter registration system. The Illinois hack, which shut down the Illinois voter registration for nearly two weeks, was covered by the news media when it happened in mid-July. The breaches are causing concern among election officials because of the voter personal information that could have been stolen, not because of any fear that an election could be stolen, law enforcement officials say. The FBI said Monday that it doesn't comment on specific alerts, but added that it routinely sends out advisories to private industry about signs of cyber threats that it comes across in its investigations. • August 15, 2016 Hotels in 10 states, including Colorado, and D.C. may have been hit by hackers Nonetheless, the revelation comes amid news that the FBI is investigating suspected foreign hacks of state election computer systems, and earlier this month warned states to be on the alert for intrusions. Entitled "Targeting Activity Against State Board of Election Systems," the alert stated that the FBI was investigating two computer attacks and listed eight IP addresses — unique numbers assigned to every computer and device using the internet — that were linked to the hacks. In July, officials in that state discovered the intrusion, in which hackers were able to retrieve voter records. In the Illinois case, officials were forced to shut down the state’s voter registration system for ten days in late July, after the hackers managed to download personal data on up to 200,000 state voters, Ken Menzel, the general counsel of the Illinois Board of Elections, said in an interview. Those concerns prompted Homeland Security Secretary Jeh Johnson to convene a conference call with state election officials on Aug. 15, in which he offered his department’s help to make state voting systems more secure, including providing federal cyber security experts to scan for vulnerabilities, according to a “readout” of the call released by the department. “Attempts should not be made to touch or ping the IP addresses directly.”

“This is a big deal,” said Rich Barger, chief intelligence officer for ThreatConnect, a cybersecurity firm, who reviewed the FBI alert at the request of Yahoo News. The events in Arizona and Illinois sparked so much concern that Homeland Security Secretary Jeh Johnson spoke with state elections officials in a conference call on August 15, trying to assuage fears of a massive Election Day cyberattack and offering up federal experts who could visit election sites and make recommendations for security improvements. In that call, Johnson said that while DHS isn't aware of any particular cyber threat against election-related computers, it's "critically important" to make sure that election systems are secure amid a rapidly changing threat landscape, according to a DHS summary of the call. The Arizona Secretary of State's Office revealed news of the hack back in late June and early July, reporting that it was a serious attack, the FBI was investigating, and that no data had been stolen.
U.S. officials are investigating the hacking of election system databases in Illinois and Arizona. The FBI alerted all election officials nationwide about this issue earlier this month.