The US Justice Department, working with the Department of Homeland Security (DHS), filed a complaint Thursday against California for its voter-registration lists, alleging that more than 20,000 people who are likely noncitizens are registered to vote in the state.

The federal government said its preliminary analysis identified individuals who may be ineligible to vote in federal elections after comparing publicly available California voter-registration records with federal immigration data. The review remains ongoing, according to DHS.

Federal law prohibits noncitizens from voting in federal elections. The Justice Department alleges that California has allowed individuals believed to be ineligible to remain on its voter rolls and claims the state failed to take action after federal officials raised concerns.

“State-facilitated voter fraud is unacceptable in the United States of America,” Attorney General Todd Blanche said in a statement.

Blanche said that if the allegations are established in court, California would have undermined confidence in the electoral system and violated laws protecting the country's representative system of government.

The Justice Department said it would continue investigating suspected voter fraud and pursuing legal action to enforce federal election laws.

DHS Secretary Markwayne Mullin said federal officials reviewed publicly available California voter-registration files and compared relevant records with federal immigration data to identify people believed to be noncitizens.

“This preliminary analysis has identified a significant number of individuals in California who are likely noncitizens and appear to be registered to vote; the analysis and review remain ongoing,” he said.

The lawsuit is the latest move by President Donald Trump’s administration to expand federal oversight of elections ahead of the midterms on Nov. 3, as Republicans face a competitive fight to maintain control of both chambers of Congress. (AA)