The Justice Department has threatened California with possible legal action over what it says are noncitizens believed to have received mail ballots for next month's midterm elections.

A letter Tuesday to Secretary of State Shirley Weber from Trent McCotter, the acting deputy attorney general, says that the Justice Department has provided officials in Los Angeles County with a password-protected thumb drive with a list of names the federal government believes are likely noncitizens who were sent ballots to participate in November's election.

The letter obtained by The Associated Press gives the state 48 hours to determine whether any citizens are included on the list.