More than 400 people believed to be noncitizens were registered to vote in Washington state, the Department of Justice announced Monday. 

The heads of two U.S. attorney's offices for the state asked that Washington election officials segregate the ballots of those who appear to be voting illegally. 

“For years, Washington State has had a mantra: our elections are ‘free, fair, and devoid of fraud.’ But our investigation shows not all of that is true – people who are noncitizens are registered to vote and are voting in our state,” Acting U.S. Attorney Neil Floyd said in a statement. 

The state attorney's office will provide a list of individuals it believes may be illegally registered to vote to the Washington Secretary of State so that ballots from those individuals can be set aside until their citizenship is confirmed.