The FBI declined to comment on the breaches against the state election databases mentioned in its bulletin.
However, in addition to Arizona, Illinois is another state that has reported a recent hack of its election system. A data breach detected in July stole voter registration records for 200,000 people, said Ken Menzel, the general counsel of the state's board of elections.
Some of that stolen data includes driver license numbers and the last four digits of voters' Social Security numbers, he said. Most of the rest of the stolen data could be bought by a political committee for a small fee, Menzel said.
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